How to remove non-essential files from Leopard
You can use Monolingual to trim the locales you don't require. This should trim at least a couple of GB.

The printer drivers are located in /Library/Printers. You can delete everything within the Printers directory (note, do not touch the /System/Library/Printers/ directory).

Additionally, if it's a default install, it may have come with iLife. GarageBand loops also take up a few GB and are located in /Library/Application Support/Garageband/Apple Loops/.

There are other areas you can trim space, but those will net the biggest gains. You can also give programs like DaisyDisk a shot (or free equivalent). They'll show you how data is distributed on your hard drive, and allow you to further pinpoint cruft that can be removed.