Hi,
I live outside London and have done so for the past 25/30 years, I have been into London twice!
I have no idea on the questions your asking but there are far better places to visit than London in the UK.
There are beautiful quint towns in the Cotswolds, my favourite place which is nearest London is Henley-On-Thames. Many Americans go there. YOu will find the River Thames, beautiful pubs/restaurants with real food. Food costs a lot more there but its well worth the extra money as its freshly cooked and not of a chain. The buildings in Henley are all old and historic.
Then, if you get a chance, catch a train from Paddington Station (London) to Swansea in South Wales if the weather is nice and catch a bus to The Mumbles. There you will find a real ocean with real waves! and a visit to Joes Ice Cream Parlour in the Oystermouth is a must (this is near The Mumbles). Its the only place, as far as I am aware that sells fresh ice cream. Its famous. The Mumbles has good pubs and restaurants, although 90% would be chain. There is one a la carte restaurant there which serves delicious food.
If time permits, visit West Wales, Tenby is my favourite haunt. To some extent it will be like visiting another country. You will find people speaking Welsh here, again its on the coast. Tenby is full of gift shops but you wouldnt be giving it justice if you tried to do Swansea and Tenby in one day from London. YOu would need at least three days. If you were planning on going by train, try booking your tickets via the internet before you travel as you can save a lot of money this way.
If you want any further info on the UK just send me a private message via my inbox and I should be happy to research and find out - excluding LONDON of course

Croissant