Which 2 are best?
 

My wife and I are visiting India in September. We are adventurous travelers, both in our 70's. Due to time constraints we will only have time to do 2 of the following 3 taxi trips. We will be hiring private taxis so only us plus driver in taxi. The three trips are as follows.
1. Srinagar to Leh trip in 3 days, changing to a Ladakh taxi in Kargil so we can sightsee. Srinigar - Kargil - Unsure - Leh
2. Nubra Valley trip in 3 days. Leh - Hunder - Pangong Lake - Leh
3. To Manali in 3 days. Leh - Unsure - Unsure - Manali.
Which 2 should we choose?
We do not wish to do any trekking, looking at scenery and architecture and culture, and photography.

I will attempt to answer your question, though it is not very clear to me as to how many days you have at your disposal for this rather hard trip. The roads have improved dramatically since the last time I was there.
a. Srinagar to Leh is nearly 12 hours by road. So you can break your journey for an overnight at Kargil. There are a couple of good somewhat basic hotels, Chuttuk Heights is one of these. Before you enter Drass you can stop at Harka Bahadur memorial for a photo op - where the road comes very close to Pakistan. The Tiger Hill, scene of the ferocious battle, is clearly visible. There are some Buddhist relics too at Drass...the coldest region! Short of Leh is the Pathar Sahib Sikh Temple and magnetic hill.
b. Nubra valley, Hunder & Pangong can be done in three days. Imo, the itinerary could be - Leh >> Khardungla >> Hunder >> Nubra valley (5-6 hrs), o/n at Stone Hedge. From there about 5-6 hrs to Pangong Tso and you can o/n there in those basic accommodations available. Come back to Leh via Changla Pass, another 5-6hrs.
c. Leh to Jispa is about 8-9 hrs or a little more. O/N in Gemoor Khar a delightful place. To Manali another 6-7Hrs.
From the point of view of sightseeing, scenery, photography & culture trips a & b are recommended.
This trip should be wrapped up by mid-September as thereafter there is a risk of early snowfall, when the passes get blocked, jeopardizing the plan.
Happy travels!

Thanks for your reply. I will change our Nubra Valley trip to 2 days an have an extra day in Ley. We decided not to rush this part of our visit to India and to do the 3 trips. The dates would be as follows Leave SRinagar 6th Sept, 3 days to Leh. 3 nights in Leh, Leave for Nubra 11th Sept, Leave for Manali 13th Sept, 3 days to get there arriving 16th September. Do you think this is early enough to miss snowfall?

I guess it should be fine. Happy & Safe travels!

Another piece of info I have picked up from a friend who has been to this area very recently is the reduction in time of travel from Jispa to Manali by almost half, due to the construction of the Atal Tunnel. You will enter the tunnel at around Sissu. If memory serves me right, this place should be just a few miles south of Jispa. You will exit the tunnel at Solang valley, some 8 miles short of Manali. In my younger days I have done this region a couple of times, trekking. The most spectacular scenery witnessed was in the area near Chota Dara. Of course, you will bye-pass this area as the tunnel goes past Gramphoo, the junction where the road coming from Tabo & Nako fetches up, before turning northwards to Leh. It is on this road that the Kee, Kibber & Dhankar monasteries are located. The road also passes through Great Himalayan Desert National Park, home to Himalayan Ibex. We were lucky to see a whole herd crossing the road and going up the steep hill, where no other animal could have found foothold!
Happy Hunting!

Thanks for that information. We have decided not to go to Pangong Lake but take 3 days on Nubra trip, going out to Turtuk and staying at Hunder then returning to Leh via Khalsar, Wari La, and Karu. From what you have told us, maybe 2 days to Manali from Leh will be ok.

I can say Srinagar is much better to cover Leh. So option 1 and 2 are best suited to you.
Please make sure to stay in Srinagar for a day to acclimatize

Select the first two
 

Selecting the first to explore Jammu & Kashmir and the 2nd Ladakh area can be the best experience. I would also suggest first checking the weather conditions and then planning it.

When you come to India again, I hope you add the destinations in the Northeastern States of India as well.