The presentation of rb2 is far superior IMO. The RB2 guitar is also much better, although thats more a matter of taste and what you're used to. The music maker was very gimmicky after trying it out in person, not something I'd actually ever use.
The GH drums are only marginally better - those cymbals are just as hard and plastic as the pads, they dont wobble like real cymbals, but overall the set is MUCH, MUCH quieter than the RB1 drums (havent tried RB2 drums).
On the other hand, GH:WT has "La Bamba", which when sang by a drunk idiot as loud and obnoxiously as possible (at 2AM, preferably in a crowded apt building), is by far the most fun I've ever had with any music game, ever. We were rolling around so hard we kept failing, and by the time we had to start over the third time - well, just imagine trying to sleep over that, thinking the nightmare is over and then out of nowhere again comes "BLAH BLAH BLAH BLAH LA BAMBA!!!" I swore someone was going to break down the door with an axe and murder us. Good times.
Other than those two things, RB2 all the way.