Sounds to me like what you should try first is to defragment your Mac hard drive, then try Boot Camp again. The "files can't be moved" error usually means a fragmented drive. Here is the Apple discussion of the problem - which says EITHER defrag your disk (easy) or go through the complex re-initialization process you describe (hard).
Defragmenting your Mac's hard disk
Most folks on the forum have recommended iDefrag:
Coriolis Systems :: Products :: iDefrag
It is not free, however, and there may be other solutions. Also, I am not certain whether it works with Snow Leopard, so if you have upgraded to SL you should be careful.
Anyway, take a long look at defragmenting and I would try that first.
Cheers