Since you are new to Linux, the standard advice you'll probably get is "go with 9.2". I'd however suggest this; since you already have 10 burned and ready, try installing it first. If you encounter a bug or any other issue that irritates you, then just put 9.2 down on top of it.
Hmmm... now theres a little voice in the back of my head telling me I should have just said 9.2
I guess it really boils down to your aptitude and tolerance for potential bugs. One thing that might make your decision easier, 9.2 has a sexy graphical install, whereas 10 beta 2 has a (largely similar, but not quite as easy to follow) text based instalation.