10 day England itinerary?

Take the train from London to either Heathrow (may be cheaper) or Oxford (easier but maybe a dropoff charge) and pick up the car there, return it to Heathrow. But with an 11:25 flight you should be at the airport by 8:25 or so, too risky for either drive you're considering that morning. I'd return the car to Heathrow the night before and spend that in a hotel near the airport. Or you might consider Windsor for your last night, with a visit to the castle the day before.

We did a 4 week drive tour of Wales and England in 2017. It was great.

Suggest doing London first, then take the train to Oxford, spend a day there, then pickup rental car, drive to the Cotswolds and do Stratford Upon Avon.

We stayed at the Volunteer Inn in Chipping Campden and used it as a base to visit Stratford Upon Avon and other places.
Consider staying there.

After ding the Cotswolds, head to Bath, we stayed at the Brooks Guesthouse and recommend it, they provide parking for your rental car. Also, dine at the amazing Scallop Shell, that has the BEST fish and chips in England.
After Bath, you could go to Bristol or even visit a some castles just over the border in Wales. Also, consider spending a few hours in Wells and Glastonbury. Then head to Stonehenge and consider visiting the amazing cathedral in Salisbury (especially if you read Ken Follet's books). If you have time Winchester is great.

I would second Dick's recommendation for staying at Windsor the day before you fly out, and then heading to the airport the next morning. Windsor is well worth a visit, and it's closer to the airport and easier to get there.

You will need a car for the Cotswolds and that area, so it would probably be easiest to rent a car at the end of your day in Oxford and head to the Cotswolds and on to your other destinations.

Since you are planning to visit Bristol, it would be a much easier route to head to the Jurassic Coast region and explore, then drive back to London (and Windsor if you follow our recommendations). You could hopefully drop off your car in Windsor.

Thank you to both you the wonderful suggestions.

I will be in England for a week before my wife flies in to heathrow. We since she flies in at 11:25am. We were thinking of going to Stonehenge/Salisbury first so that my wife could rest bit in the car. This ofcouse means getting a car in heathrow and returning it in heathrow coming from Oxford.

This works allow us 4 full days in London and figure back home the following day.

What do you guys think of this?

The problem with driving your wife from Heathrow is that with jet lag she will almost certainly fall asleep and that will just delay her getting over jet lag. It's much better to be out and about in the fresh air staying awake as long as you can on day 1 before an early night. For most people that seems to be the quickest way to get used to UK time.

Our reasoning was similar, we thought that she could just rest a tad bit during the drive on the way to Stonehenge. Another concern was that visiting London first with having luggage would be difficult unless we went to the hotel first. Just seemed optimal to have the luggage in the car not waste time going to the hotel in London. Google shows the drive to be about an hour. We were thinking 2 to 3 hours for Stonehenge and early to bed in Jurassic Coast.

We do like to idea of visiting Windsor hopefully we will have some time for it @dick
Thank for the Wells, Glastonbury, Winchester and Wales ideas @geovagriffith

It makes sense that we pick up the car at the end of the day at Oxford if we were going this way. How about returning the car at Oxford when we get there and taking a train to Windsor? The only issue with that is that we will have our carry-ons with us in Oxford and that will be annoying which is why we thought it would make more sense to drive to heathrow at night and take a train to the hotel and spend the last 4 days in london. This resolves the carry on issue @Duluth

Would love to hear more feedback.

Kind regards