Have you tried inserting the Snow Leopard Install disc and using Startup Manager to select the Snow Leopard disc as the startup disk? Once you get started up from the Snow Leopard Install disc, the rest of the instructions can be found in the manual for your MacBook Pro. Here are the ones for mine:
Installing Mac OS X and Applications — New Hard Drive
from http://manuals.info.apple.com/en_US/MacBook_13inch_HardDrive_DIY.pdf
To install Mac OS X and the applications that came with your computer, follow these steps:
1. Start up from the Mac OS X Install Disc 1 that came with your computer, and choose your language.
2. From the menu bar, choose Utilities > Disk Utility.
3. Open Disk Utility and select the new drive in the list to the left. Note: If you are formatting the primary drive, use the Disk Utility program on the Install disc.
4. Click the Partition tab.
5. Click on Options, and verify GUID is selected if this is the startup drive.
6. Name the volume “Macintosh HD.”
7. Apply the change by clicking the Partition button.
8. At this point, either
• Quit the Disk Utility application, and proceed with the Mac OS X installation. Follow the
onscreen instructions. After selecting the destination disk for installation, continue following the onscreen instructions. Your computer may restart and ask you to insert the next Mac OS X Install Disc 2.
or
• Leave the Disk Utility application open, and restore the backed up files from the image
you created before removing the hard drive.
Installing Applications
To install just the applications that came with your computer, follow the steps below. Your computer must have Mac OS X already installed.
1. Back up your essential files, if possible.
2. Insert the Mac OS X Install Disc 1 that came with your computer.
3. Double-click “Install Bundled Software Only.”
4. Follow the onscreen instructions.
5. After selecting the destination disk for installation, continue following the onscreen instructions. Your computer may restart and ask you to insert the next Mac OS X Install Disc 2
6. Restore the data by reinstalling the backed up files from your backup to the new drive.