BIOS and Hard Drive Recognition ?

I have a Dell Dimension 4600 and I have just installed a new hard drive (old hdd dying) and placed the OS (XP) on that drive... the new drive has been formatted as Drive F:... when I go into the BIOS to select this drive as the start up drive, I only have a choice of Drive C: for the start up boot drive... the BIOS does show the new hdd and the system does start up properly... however, I need to see if I can recover data from my old hdd partitioned as C: and if I connect the old C: drive up, the system tries to boot off of the old C: drive (old hdd has bad sectors that does not allow the OS to launch - blue screen on start up)... is there any way to get the BIOS to boot off of F: and ignore C:... thanks.