Traveling input for Geneva > Chamonix > Paris?

The easiest way to get from Geneva to Chamonix is to use one of the Shuttle services. They pick up both at the airport and the train station. Have a look at this page for information.....

http://www.chamonix.net/english/transport/shared-transfers

Use the same method to get from Chamonix to Geneva rail station, and then take a high speed TGV to Paris. Those travel at up to 300 km/h, which will get you to Paris in as little as 3H:08M. Note that you'll likely be arriving at Paris Gare de Lyon, so you'll have to use Metro or Taxi to get from there to the area of your hotel (there are about six major rail stations in Paris).

Rather than renting a car, I'd suggest using the high speed train so you can maximize your touring time. There's a LOT to see in Paris. Note that for driving in France each driver listed on the rental form will require an International Driver's Permit, which is used in conjunction with your home D.L., or a certified translation of the terms of your license in French. Either of those is compulsory for driving in France. Other things to be aware of is very strict speed limits and automated speed cameras (if you're nicked for speeding, you won't know about it until after you get home), tolls on the motorways, etc. I would not recommend driving in Paris!

Geneva to Chamonix is real popular route so there are multiple options. Not necessary to rent a car to drive there There is Shuttle from the airport it only takes under 2 hours. Here is the site:
http://altibus.com/

You are going in October you are lucky no problem with crowds. Everybody is back to school back to work in September.

Take the train Chamonix to Paris (it is a popular route). It is high speed rail one change in St-Gervais-les-Bains. Takes a little under 3 hours.
You may drive with a valid U.S. driver's license if it is accompanied by a notarized translation in French. It is strongly recommended that you carry an International Driving Permit.
Here are the details;
http://franceintheus.org/spip.php?article376

I would stop in Lyon on the way to Paris from Chamonix.

And someone will chime in hear on where to eat and where to stay.
It all depends on what you can or can not eat and what you can afford to spend to stay.

And I echo the above don't be trying drive in Paris
Also the rail is superior to what you may be use to here in USA with Amtrak i.e. the trains go faster than the cars in Europe.

You can rent a car in Geneva with French plates. Since the airport sits on the Swiss-French border and there is a "French" part of the airport where you can rent a French car. So if this sounds lie something you want to do, there is nothing stopping you. Keep in mind that fuel prices are at least double the US price, and the super highways generally have tolls. Speeding tickets are issued by robocams, so you don't find out about them until you are home. First the rental car company dings your credit card for $50 or so, but that is just the service charge for giving the police your name and address. The ticket shows up months later.

Chamonix might be getting some snow in October, so be aware of that.

Beaune is a nice place to stop, just south on Dijon. Its in the middle of the Burgundy wine region, and in October they should just be wrapping up the grape harvest.

Do your friends live in the city, or outside? Will you be staying with them, or getting a hotel in the city? If you are going to be staying in Paris, drop it in Dijon and take the train from there.

Of, course, you could do all of this using trains and the Geneva-Chamonix shuttle. Lyon, Beaune, Dijon are all on the train routes to Paris. Usually, I only rent a car if I can't do it practically with public transport. Train can be a very relaxing way to travel, not at all like airplanes or buses.

Just to clarify one point.....

" It is high speed rail one change in St-Gervais-les-Bains. Takes a little under 3 hours."

Many of the trains are direct (no changes) such as the one I mentioned in my earlier reply at 3H:08M. Check the schedules and be sure to pick a direct train rather than one with changes.

Yes, it is at least 5 1/2 hours Chamonix to Paris. The fastest are a couple of trains a day that starts with the narrow gauge line to St Gervais les Bains, then a TER train to Bellegarde. That takes 2 hours and 55 minutes before the Geneva-Paris TGV stops to pick up passengers and then it is nonstop to Paris Gare de Lyon.