itinerary help : if i want to do all I can in Interlaken and i am handicapped

Interlaken is a good base to travel around the places you mentioned....Jungfraujoch, schilthorn, harder kulm, launterbrunnen valley , trummelbach fall, lake briens , lake thun. Just get the 7-day Swiss pass at Zurich airport or any major train stations in Switzerland on arrival. This will allow you to travel on train, buses, and boats too with the exception of few destinations like Jungfraujoch for which concessional tickets are available at the station.
However, Interlaken is a big town. If you want to enjoy nature and scenery, stay in Lauterbrunnen or other smaller towns.

For the TGV trains, such as Paris-Basel and return, you'll just have to buy tickets there at full fare if you can't book online, about €120-140 per person, each way in 2nd class. Buy roundtrip train tickets as soon as you arrive, in case some small advance discount is still available for the return leg. Or compare flights at www.skyscanner.com if you would consider buying a plane ticket at the airport.

The Swiss Travel Pass is sold easily at train stations in Switzerland, such as at Basel, and is offered for 3, 4, 8, or 15 consecutive days or for 3, 4, 8, or 15 travel days to use during a month. For instance, 8 consecutive days costs 363 CHF per person. While I don't like to force a trip to fit a rail pass, 8 consecutive days sounds like a good match.

The Berner Oberland Pass for 8 consecutive days costs 340 CHF; it gives you more coverage on the Jungfraujoch route, but does not cover your first likely leg within Switzerland, from Basel to Bern and return, a value of 40 CHF each way.

So i loose discount on my first leg of my travel from Paris, couse no one said it is possible to buy it from paris train station.just thing that ramain is my socond leg ( back to paris).now bernese oberland pass is better or swiss pass?or i can buy just paris -basel , then in basel , buy a swiss pass.
2
Seven days is not much for doing what i want? How much time i need to do each of that activities i mentioned ?

The Swiss Travel Pass does not give you a discount on the TGV train ride from Paris if the train starts or ends at a border station like Basel or Geneve. Those trips are entirely within France, according to the train rules. (There's no benefit to riding a TGV all the way to Zurich; it's not the fastest connection point on the way to Interlaken.)

I would plan to change trains in Basel, buy the Swiss Travel Pass there, and start using it right away for full coverage to your Swiss destination. The Berner Oberland pass has some advantages and the Swiss Travel Pass has it's own advantages, both at a similar price. You can probably do a lot of mathematics and still not come out with a clear winner. The Swiss Travel Pass sounds easier to me.

Other people can offer opinions about how much you can do if you plan for 8 days in Switzerland. I know for sure that people do visit both the Schilthorn in the morning and the Jungfraujoch in the afternoon of the same day, when necessary. But it you can give each of those a separate day, then you can fit in more stops on each side of the valley, and in the lower level of the valley.

Are you wondering about making the whole trip more than 10 days? Or trying to allow more time in Paris within those 10 days? Or just trying to decide whether or not to book a hotel stay in Lausanne?

Dear,
Thanks alot for your help. Our trip will start at August 25 and ended at Sep 4th, based on our flight ticket. Thats all, no more, no less. we want to spend the whole in switzerland.

first i thought 4-3-3, i mean 3 nights in bern, 4 nights in interlaken and 3 nights in laussane or geneva. But then when i saw what different things we can do in interlaken, ( like cycling, and lake crouse , and Jungfraujoch, ........) change my plan to stay more in there, and do as much as I can based on my leg problem, for instance 7 nights or 8 nights , and leave 2 or 3 nights for bern or laussane. Now i am in the position for book hotels, and perhaps it is a little late, but i didnt deside.

I really like bern, but because we must back to paris to catch the plane at 16:00 sep4, i found if i go to Lausanne or geneva, it is easier to reach paris.

The important question is ramained, how many days in interlaken, and i devide it to 2 parts, 4 night in interlaken and the rest in launterbrunnen, or all in interlaken. We prefer lively nights, of course, by lively , i don't mean crowded, just 2 bars and two restaurant near each other will be fine.

Ps.... if i catch the 4.23 pm train from paris to basel, 7:26 inBasel, 33 minutes is enough to buy swiss pass and ticket for the interlaken, catch the train 7:59 to interlaken? I am

Thanks for including your travel dates. Now I see why you are looking at TGV trains going past the Swiss border. For the 16:23 departure from Paris, I understand your concern about having enough time to buy passes at Basel station. If you miss that connection, the next direct train to Interlaken is one hour later.

It would be simpler for you to get the later TGV, which departs Paris' Gare de Lyon at 18:23 and runs direct to Interlaken (only one direct train per day) arriving at midnight. You would buy this whole ticket and not buy or use a Swiss Pass until the next day.

And yes, if you need to get to CDG the same day, a TGV departing from Geneve or Lausanne between 6:00-7:00 a.m. does look like your best train option. Or flying can cost less! Air France flies from Geneve at 10:30 on Sept. 4, arriving 11:40 at CDG, about the same time you would arrive by early train + airport bus. Current price is $41 US and even if travel agents near you don't sell TGV tickets they might sell this plane ticket. No matter what, I hope that you are packing light luggage to make these connections easier.

Interlaken works for your late arrival, and for Harder Kulm and the lakes, and is only 20 minutes from Lauterbrunnen or one hour from Bern. It's not necessary to change to another hotel, but I would prefer to spend 2-3 nights in Muerren, where you can wake up with the best mountain view.

Very good information, now I can decide what to do.Just one thing remains, some comments says interlaken is a tourist trap, and places like Wilderswil or Unterseen or Muerren is better.Ok, if I want to stay in other place, which one is better , note that i want to stay 6-7 days and go and see all places, with cable car, crouse or walk or cycle, and i must be somewhere in the middle of all activities , moreover we want to rent a bicycle for 1 or 2 days and wandering so we must be almost in flat place ( because of my leg, slopes is hard for me)
Where?

I would recommend staying in Murren instead of Interlaken, but the "flat" areas of any of the mountain villages will be limited. You might consider Lauterbrunnen. It is outside of Interlaken in the valley below Murren and Grindwald, so it is relative flat. The town has nice accommodations, restaurants, and is a transportation hub for trips into the mountains on either side of the valley.

I am thinking of how beautiful everything is in Muerren - aaahhhhhhhhh - but then I do remember that while getting to Muerren is level, level on the train to Lauterbrunnen, 2 or 3 steps up to the cable car to Grutschalp or fewer, level onto and off the cable car, slight slope up to the Grutschalp train, 2 steps onto the train, and a way out of the Muerren train station without steps, I do remember how steep it is from there into the village - quite steep and for some perhaps 200 or 300 metres, then downhill again on the other side. Unless you stay at the one of the three places at the station it could be difficult.

Wengen across the valley, reached by a cog railway from Lauterbrunnen, is - as I remember - much more level, yet still with a gentle slope.

Lauterbrunnen is mostly flat at the train station end, but gets a bit of a slope on heading towards Stechelberg. Then the valley floor is nearly level, but with a very very gentle slope towards Lauterbrunnen for the river which collects all the waterfalls.

As an able bodied person and often in a car, not on a bike, I've not really paid attention to the slopes.

I'm picturing all my trips there in my mind's eye.

Trumelbach falls has a lot of stairs. Keep this in mind when choosing activities. I was a little concerned to see it on your list after you mentioned some of your challenges.

As I got, Launterbrunnen is more flat.But by flat , I mean I can access to other parts, Interlaken city and lakes( thun and brienz) by bycycle.from my b&b to there and back, as far and as much as possible.