Just try to stay somewhere in the Westend and it won't take you long to get to Kensington-Olympia by tube. The Hilton is obviously fine, but if you're on a budget, have a look at some of the smaller hotels like
Cheap hotels at london, London hotel reservation, Discount london hotels by Shaftesbury Hotels London. They offer great value/money, and although the rooms are often a bit on the small side, most of them have been renovated very recently and feature flatscreens and other stuff.
Don't think I'll go, I'm just to "new" at this...but if you need tips for London, let me know, I live here