Buy Mac OS X Server from the App Store if you are using Lion (and download Apple's server admin tools so you can run Server Admin), or try out JAMF software's NetBoot Appliance (that will run as a virtual machine, under OS X, Windows, or Linux), and (hand waving here you might be able to use "System Imaging Utility" in the server tools) set up a NetBoot image of your installer DVD to install the software. You could set up NetBooting to send an image file for the computer to boot up from over the network. Just a wild thought that I'll throw out, but would be more trouble than it is worth for one computer, and it well beyond the scope of what you really want to do.
Make a Bootable Mac OS X 10.7 Lion Installer from a USB Flash Drive.any suggestions to get this External USB OPtical DVD DRIVE to install OSX 10.6 will be much. Boot SNOW leopard 10.6 Installer via DVD USB -external drive.
How to Create a Bootable Mac OS X USB Disk Boot SNOW leopard 10.6 Installer via DVD USB -external drive.I've done a bit of searching, and found these two articles: