verifying dmi pool data

hi,ive been trying to dualboot my pc with win xp..my pc has vista preinstalled,..ive made ia right mess of it ..so i thought i would just load my backup disc to get it back to factory default settings and everything would be ok..so i put my backup disc in and pressed f12 to get into the boot menu,from there i got 4 options,removable/hard disc/cdrom/network...i selected cdrom,then it went to loading ramdisk image,..i then selected the language/restore to factory default/then click ok...after a few minutes i got a message saying "restore failed-reason..0xa0000003..then it said click to restart computer...then it went to a black screen with a message saying."verifying dmi pool data...its been running for 15 minutes but nothing semms to be happening..how long to i leave pc on this "verifying dmi pool data"...hope someone can help me out with this problem..the computer is a standard acer e380 deasktop... ???FORGOT TO MENTION WHEN  I PUT THE XP DISC IN I GOT A MESSAGE SAYING C DRIVE NEEDS TO BE FORMATTED IT SAID THAT IT WAS RECOMMENDED..SO I HIT THE OK BUTTON...no i cant get my recovery disc loaded to take it back to factory setting's...thanks theted