Looking for help to finalize a Scandinavian tour for 15 days in July (Denmark, Norway maybe Sweden)

If you haven't bought your tickets yet, look into flying into Oslo and out of Copenhagen. It will free up some more time

Well it's two very different options, so I understand it's hard to choose. The Swedish option has more cities, whereas the Norwegian one is more nature and fjords, it's hard to compare, so in the end it depends on what you like the best.
The Swedish part looks good, so I will mainly comment on the Norwegian part.
Since you write that you will drive, I assume you have a car for the whole trip. If you decide to drive, pop by Helsingør and check out Kronborg slot (famous from Hamlet). It's from the same period as Kalmar Castle and is similar in style. Then take the ferry to Helsingborg in Sweden. You can also se it as a day trip from Copenhagen.
However you can also take the overnight car ferry between Copenhagen and Oslo, to save along drive, with possible jetlag.
Oslo is the least interesting of the Scandinavian Capitals, so if you need to, you can cut some time there.
You only have one day for Jotunheimen, why is that? There are few roads, so the area is best seen in a pair of hiking boots. One of the most popular day hikes is the Bessegen ridge.
You can also extent your trip a little to the absolutely stunning Geirangerfjord.
I haven't been to Bergen, so I have no comments there.

Regarding distances and drive times it's mostly and issue in Norway, where you have to go around the mountains and fjords. But also keep in mind that you have a lot of daylight hours, so you don't have to worry about getting to you destination before nightfall.

I agree with Morten that it's a tough call. I think the beauty of Norway's mountains and fjords is extraordinary, and Bergen is delightful, but if this is going to be your only visit to Scandinavia, as you suggest, I think Stockholm is essential. However, even in Option B, you're not allowing enough time to do it justice.

I guess I'd lean to option B, with one modification. Assuming you're locked in to arriving and departing from Copenhagen, I'd head directly to Stockholm on day 2. (I enjoyed Kalmar, but I wouldn't sacrifice time in Stockholm to go there.) If you are still working out the air portion, fly into Stockholm and out of Copenhagen.

I also agree with Morten that Oslo is less interesting than Stockholm or Copenhagen, but i wouldn't spend less than two days there. There are some terrific museums, the city hall, the Vigeland sculptures at Frogner Park, more than you could do in a day.

Overall, it's a fast-moving itinerary, and you may find yourselves wishing you had more time to see some of the places than you do. But if you feel confident that you can do it, I think you'll enjoy either itinerary immensely.

You've got a lot of really long drives in both itineraries. I'd consider some adjustments.
Have you already bought a RT ticket to Copenhagen? If not, I'd suggest flying into Stockholm, Oslo, or Bergen and returning from Copenhagen to avoid backtracking.

I'd also suggest that you use a car only in Norway and take advantage of a cheap flight or the ferry to avoid some long drives.

For option B, I'd suggest
1) Fly to Stockholm and start your trip there. (3 nights)
2) Fly to Bergen two days. (2 nights). You could even do the nutshell option that is round trip to Bergen. Pick up a rental car on departure.
3) Visit all the various sites in Norway, finishing in Oslo. Drop off your car in Oslo. (6 nights in Norway)
4) Take the overnight ferry from Oslo to Copenhagen (1 night)
5) Copenhagen (3 nights)

Similarly, for option A, I'd only use the car in Norway after departing Oslo. I'd take the overnight ferry between Copenhagen and Oslo and fly from Bergen back to Copenhagen rather than backtracking.

Thank you all so much for the great suggestions. We already have airplane tickets for CPH so we cant change that. I will post the final plan and impressions when we are back in July.

The drive from Copenhagen to Oslo is extremely boring. 6-7 hours on a highway at 60-75MPH (100-120 km/h). No great scenery (at least very limiting).

What about flying from Copenhagen to Bergen, and do the Norway trip in the oposite direction, ending in Oslo, and from Oslo take the nightferry back to Copenhagen.

1- Arrive in Copenhagen
2- Fly from Copenhagen to Bergen (you can do this the first day also, It's a 1 hour flight. The you will get one more day in Bergen)
3- Bergen
4- Now you need to choose. Will you 1) rent a car and be free, 2) take the scenic Bergen-railway, or 3) hop on the fjord cruise on the Sognefjord to Flåm
5- A day deep in the fjord area somewhere, depending on your transportation
6- Another day deep in the fjord area or in the mountain area, depending on your transportation.
-If train: Stay somewhere along the Bergen railway or the Sognefjord
-If car: Maybe drive north-eastwards on the Sognefjell-road (mountain pass above 1400 metres)
7- Heading towards Oslo.
-If train: Flåm-railway and last half of the Bergen Railway from Myrdal to Oslo.
-If car: Gudrandsdal valley (maybe the Peer Gynt road) Maybe stay the night in Lillehammer.
8- Last leap to Oslo
-If train: You arrived probably in Oslo already the day before, so a whole day in Oslo.
-If car: The drive from Lillehammer to Oslo takes aproximately 2 and 1/2 hour. The first half our or so you drive along and over the lake Mjøsa. The rest of the drive is a not very scenic highway.

9- Oslo
10- Oslo
11- Halfday in Oslo, Nightferry to Copenhagen departs 4:30PM.
12- Arrive in Copenhagen at 10:00AM

I would recommend option B.

I also agree with Andreas that you should consider the train or flying.

We also used Copenhagen for the to-from to Scandinavia. We took the train to Kalmar and picked up a car at the train station (you have to arrange for the car to be at the station as no rental dealers at the small station) to spend 2 days in the glass country. If you are a fan of glass it is a great place to spend a day or 2. We visited several small glass makers.

We flew from Kalmar to Stockholm to save time. Stockholm is well worth 2 or more days.

The Norway in a Nutshell is a must. We stayed in a hotel located at the first stop on the Flam Railroad - the Vatnahalsen Hoyfjellshotell. If you like hiking and mountain biking it is the perfect place to stay. You can catch the Flam Railroad at the hotel and it stops there on the return trip. We made several trips to the Sognefjord.

We flew back to Copenhagen from Bergen - an easy flight.