It depends on what package you get but the main one comes with one guitar, one microphone, and one drum set
yes they do
No. Wii rock band instruments can only work on the wii
You can play band hero instruments with rock band 2.
No unfortunately the instruments for rockbands are platform specific.
yes of course why not
most probably
yes if its on the same system
probably not
Yes, the instruments require batteries.
About $250.
Yes they do. i know from personal experience. i got rock band 2 for Christmas, then i wanted to get rock band 2, so i got just the game. and guess what! the rock band instruments worked! Now that Rock Band 3 is out do the Rock Band 2 drums work or do you need the ones with cymbols?
I have the Wii versions of both games, and my instruments work fine with rock band 2.