to make a new install, put the disc in the drive, and click reinstall... before it goes through the process, it asks you where you want to install it (default is C:\Program Files\Activision i think) - simply create a new directory like C:\Games\BC Install 2 (or whatever you want to name it and where you want it to go) and install it from there... then it will ask you if you want a shortcut on the desktop, click yes and your new shortcut will point to your new install with the new name of your install...
putting spare on b-drive? dunno... i guess try it and see?