Apple Disk Utility Repair Required

Can someone please advise me how to use the Apple Install Disc to run the Disk Utility application on my custom built Mac running Mac OS X Snow Leopard. I have included a screen-shot of the error message after testing my Mac OS X startup disk. Thanks for your assistance in this matter!

That screen grab is too shrunken to read.
I'm guessing it's telling you that there is filesystem corruption on your boot disk and you need to boot off a different disk (e.g. the Apple install DVD which is only going to work if it's a Real Mac) to repair the filesystem.

In these cases my S.O.P. is to either boot off the clone of the boot disk (you do have a recently-updated clone partition don't you? ) or to use whatever install media you have (e.g. with ML you could use a UniBeast USB stick) and instead of actually re-installing, go to Utilities->Disk Utility and do the repair from there. I haven't put SL onto a CustoMac so can't give you details, but you should be able to follow the usual installation method just look for Disk Utility before any of the actual installation steps.