Yeah, that one I bet will be easy, though it does have that little soloish bit at the beginning. I think "Say It Aint So" would have been a better Weezer pick.
Funny that you say that, because I'm about 99% sure that's going to be a Rock Band song.
However, I'll definetly be buying both. Cherub Rock? Fucking radical. My Name is Jonas? God damn. Excellent songs right there. I heard the bass heavy Suck My Kiss is in it too by Chili Peppers.