Another food suggestion: Sofra, Turkish, near covent garden. Good food at great prices ... and it gets absolutely packed so get there before 6.30pm. I'm sorry, but I forgot the street it's on.
As a brit living in the US I think that restaurants tend to be more uniform in the US. Restaurants in England can be very bad, particularly in London, but equally, they can be very good, and not too expensive. However if you "chance it" in London, I'd give you less than 50% odds of getting a great meal, so go for personal recommendations.
Musically .. I'm sorry to say that not much seems to be coming out of the UK these days, apart from Radiohead and a few others. I'd have to say that the US would be a better bet for new bands. Just IMHO. Oh, and the CDs are horribly overpriced as well.
I still love London .. for me the most exciting city in the world, and one of the most accessible.