Check the CD to ensure that it's clean and scratch free. If possible, try copying it to your hard drive and running it from there.
Thanks for the quick reply. I thought that, too, so I checked my cd. looked fine, but I tried my roommate's winxp cd just in case (and tried it in both dvd drives)...and got the same error as well. Keep in mind that my computer POST just fine and all attached devices are detected by the BIOS.
So I have one more question. When the "file aic78xx.sys is corrupted" error comes up, is that one of the files being loaded into memory from the setup cd, or is that something already on the system and is just being utilized by the drive for setup?