Hi AmionKid, i just got the same problem here in a mac but i could sucessfully jailbreak my iPhone 3G.
Before my iDevice entered (or tryed to) in DFU mode, redsn0w just says that is waiting for reeboot, so i pulled of the cable and fastly inserted again. Worked perfectly. :)
Some guys say that i am crazy, but it worked to me. (Do it at your own risk)