You can use your Snow Leopard disc however the easiest way to do it is:
1. Get an enclosure for the drive and put the new disk in. When done connect to the MBP.
2. Then use Disk Utility to format the new drive as Mac OS Extended (Journaled)
3. Using Carbon Copy Cloner or SuperDuper to clone your internal drive to the new drive.
4. After this is done swap the drives i.e. put the new drive in the MBP and you can use the old drive in the enclosure and use it for a backup disk.
If you want to start clean then simply put the new drive in the machine, use Disk Utility to format from the SL disc and then install SL onto the new drive. From there you can restore your data, settings and applications from Time Machine. If you choose this route here is a tutorial that shows how to do it, it's amateurish but it works just fine.
http://www.youtube.com/watch?v=z0K-mD8rAyA&feature=related
Roger