Any weird sound from it?
Can U open any cd/dvd? Can My computer see it?
Have U tried other dvd ?
Recheck your burning program speed settings.
See if it works on another user.
Check Event viewer for cd related errors in control panel>administative tools>comp management.
Check Device manager . Does it seem ok? no errors or anyhing related to it?
Try it "outside' Windows to see if the cd/dvd rom is the problem.
Try to see if you can boot from a Win cd (bios- change boot order). If you can, then it's a software related problem.
Try uninstalling and reinstaling the burning program. Try a different burning program. Do you have Nero? if not, give it a try.