Fun stuff in LA

So LA has a lot of fun things to do. If you want a real tourist experience, I would highly recommend either Universal Studios or Disneyland. Universal is my personal pic, because there are lots of different things to do and the city walk is a great place, with a ton of restaurants, shops, movies, IMAX, etc.
If you're interested in some comedy, there's an improv club on Hollywook Blvd called IO West, and it's amazing. They have multiple shows every night of the week, although usually the best are on thursdays and saturdays. The best part is that they have a lot of free shows and tickets to the other shows only cost $5-$10. Go to iowest.com and there's a schedule and information. Also, there's great standup comedy venues, like the Laugh Factory or the Improv (which ironically does standup and not improvised comedy).
In terms of food, there's great places to eat everywhere. If you are in West LA, I'd highly recommend Shanghai, Milk and Honey, Nagila Pizza (they have a large menu), and Jeff's Sausage. They are all excellent.

Enjoy LA!