I will say it before someone else does...do a search on London hotels in the forum since there are numerous posts on this topic.

I would personally recommend the Renaissance Chancery Court. Great upscale hotel (probably one of the best in the Marrriott chain I have ever stayed at! Yes, I stay at a lot of them!), good location within walking distance of the main shopping areas and 1 block away from an Underground station in case you don't want to walk. Restaurant was being renovated when I was there in March so I cannot comment on that. I was there on an award stay and will definitely go back again!