is this question 100% serial?
London is one of the largest and most culturally diverse cities in the world, sooooo theres craploads to do here. (yes im living in London for a year.)
umm, okay, stuff to do:
1. big ben
2. london eye
3. tate, tate modern, nationally gallery
4. tower of london
5. natural history, science, victoria & albert museum.
6. covent garden
7. pubs
8. soho
9. clubbing
10. picadilly circus
and all the other touristy stuff... basically youll struggle to not find things to do.