I guess you'll visit the village of Conington too, the church has a memorial to the 457th as well.
If you're staying in the area near Glatton or Peterborough Business Airport then there's always Duxford (Imperial War Museum) just a few miles south, and always Cambridge to view the old university town with it's architecture and quirky shops to keep the wife happy.
Other than that England is full of stuff to do, and every town is just full of eateries and coffee shops it seems. Peterborough has a nice Thai restaurant on an old barge on the river and a nice cathedral. The East is full of National Trust houses and land where you can explore the past or just wander the countryside. If you like hill walking then you'll need to go further west and north to the Peak District (only a few hours on the car) and the countryside there is stunning.
I haven't been out and about the area for a while so things may have changed but the internet is our friend in these matters. Just remember the weather coming up to the winter months can be a bit wet, especially on the fens. My grandparents used to life just a few miles north of there and I hated visiting in the winter, the place is so flat the wind has nothing to stop it.
ETA: Just reread your post and spotted you might be staying in London for a while. If you're in the London Area then you have the whole East of England and south coast to explore, the war history in the SE is everywhere and if you can get along to Portland on the south coast there is a rather nice if small museum dedicated to the US D-Day effort in the area (you could fit in Stonehenge on the way but be warned it is not as impressive as the pictures would make out, but I guess it'll be on everyone's tick list somewhere - if you're of a mind you can view it from the car while passing and be done with it
).