1. I am sure there are people who do, I personally like too record my vocals inside Protools, after finsihing my music creation in BB. I add eventually some extra instruments there as well. If you don't have any other program (you could also download some freeware) you could also try realband, this way you got a bit more overview to what you are doing. I did not work with it in fact, but I bet others can tell you much more about it.

2. By interfaces you mean external soundcards or amp simulators?

I'll be back...