Yes. But if you have an upgrade disc you'll want to leave the vista partition intact to do the upgrade. Even when doing a fresh install with the Upgrade disc (which is recommended) you need to prove you had an OS which can be upgraded with the disc. The Clean Install will get rid of the old Vista installation for you though. If you have a retail or OEM disc you can blank the drive first.
The Following User Says Thank You to poppameth For This Useful Post: