On another note, I'm up for suggestions - theme park and otherwise - for things to do in Los Angeles.
You should do all the theme parks if you can (DLR, USH, MM, & also it seems you're already planning Knotts)
In terms of other things in LA, that's completely an open field, lots to do, just depends on your time frame & location
I would prefer Magic Mountain over Knott's, though we decided the drive and traffic just aren't worth it.
We've seen Disneyland and Universal Studios before, but we'll probably check out California Adventure to see the new rehab.
As for other attractions, we definitely want to check out at least one of the comedy clubs since we're both avid stand-up fans. We'll probably end up touring some of the architectural highlights, markets, and nightclubs, as well.
Walt Disney World's Magic Kingdom
Disney's Animal Kingdom
Disney's Hollywood Studios
Disney California Adventure
Universal's Islands of Adventure
Universal Studios Florida
Universal Studios Hollywood