Urgent help needed on a 2010 Mac mini!

Help! My wife's Mac mini started acting funny and so I thought I would replace the hard drive. Got a new hard drive and installed it following the iFixit guide. But now, when I try to install Snow Leopard from the OS X DVD, the Mac crashes. I get the "gray screen of death." I've also tried installing from OS X Leopard and although it doesn't crash, it also just doesn't read the disc. I've tried both discs several times. It just won't load either disc. I've also tried swapping out the RAM to see if a bad memory module was the culprit. Please help me get this thing fixed. I've worked several Macs before, but I've never encountered this problem. Thanks.

EDIT: Solved. Although I used a Lion Recovery flash drive installer to restore (Snow Leopard) from Time Machine, I'm certain that the solution was in fact using the original media. Thanks, dethbunnynet.