Couple of things.
First, before you give up on the old drive, try a boot repair. Hook up the old drive on its' own as Master on the Primary connection. Make sure you have CD drive as first in boot order in the BIOS. Pop in the XP cd and boot up. Start the installation process. Eventually, you will reach a Repair option. Choose Boot Repair to see if it restores your old drive to bootability.
Second, unless you're gaming, what was the reason for you to change video drivers? The native driver in XP should have been okay. Since you're practically brand new on the second drive, just wipe it out with a boot diskette, and start over with a new install.