I believe that the system requirements listed by Apple are there to keep some folks from complaining that the system is deadly slow on older machines with small RAM, etc. You know they would complain, too.

Who would do a thing like that? Surely not you or I.

I was wondering if the Firewire requirement is basically to allow booting from a larger external HD. Mac OS X has a significant footprint compared with those older internal HDs.
Who serves his fellows, is of his fellows greatest - Chingachgook (by legend)