Films + Clone Wars = canon
Anything else I pick and choose without declaring it canon; I like some characters like Mara Jade and some other stuff, but somethings I outright dismiss as even being related--how some things get by with the Star Wars name I'll never know. Personally I can't stand the Solo twins, and for me the yuuzang-vong whatever the heck they're called never existed--but I love, for example, Shadows of the Empire. So for me I glean what I enjoy from the EU, but really don't consider it canon.
In reality, however, nobody can say "this is" and "this isn't" with Star Wars. It's all (gasp!) make-belive, so really it's whatever you want it to be. That's why it has so many fans; Lucas universe is so vast and complex that you can add or take whatever you want from it and it's perfectly ok because it's your imagination. For somebody to say only this and this is accepted only applies to copyright laws, not the way I perceive and enjoy the Star Wars universe.
some of them are 
