lost product key/1st & main problem

i am trying to revive my 5yr old ast computer for my 8yr old son. formatted & fdisk'd then realized the win98 key i was tring to use didnt match. that key goes to a disk that is scratched & unreadable. next i tried to load the recovery disk (win 95). comes up encrypted. next tried a win95 cd. everything goes fine until it starts to copy files/at which point it cant copy cabs/could this have to do w the different ways disks are formatted or fdisk'd for win98 vs win95-(fat16 vs fat32)--as it prompts me to reformat each time i change. i also get a 'nvram invalid...nvram cleared' msg. isnt this just the battery gone dead? frustrated & impatient/dont want to wait til mon to call microsoft....who's probably going to tell me to call ast etc. i'm tempted to load win98 on my new (this) comp just to access the key. but that would be a major pain. i know enough about comps to drive myself nuts/not much about dos/so keep any replies in a step by step fashion please. thanks!