Use something like Partition Magic and format that drive as a Linux partition. If it's unformatted or it's not based on the NTFS, you wouldn't need to do that, just load the drive in windows and resart the computer with the cd in the tray.
Then you would just load up the linux CD's and when you get to the part where you choose the section where you choose what drive to install it on, just select that drive and continue the install
Good Luck
