Vista Installation Problem

I'm having a problem where (with a completely fresh computer, just finished putting it together) as I first begin to install Vista 64 ultimate from the disk, it goes through the initial "old" loading bar, proceeds to the new vista loading bar, and then finally arrives to the Vista background with my mouse cursor and nothing else. It simply stays at this screen. The HDD is not doing anything at this point. Any ideas, i'd REALLY love to get this computer running after having to RMA 2 parts already >.<! Thanks!

I have already tried
-another optical drive for the boot disk
-only using 2 gigs of ram (heard this was a problem)
-simply letting it sit for a while

Try letting it at that blue-ish screen for up to 10 minutes, i had the same issue, i thought the instalation just hanged but it literally just took 5 full minutes to finally do something

Edit: oh and the ram problem is usually voltage issues, just to make sure, check the voltage requirements for your ram through the manufacturer's web site, and make sure the motherboard corresponds, or else phantom restarts or constant crashes will be your new best friend. Mobo's usually default dishing 1.8 volts for ram i believe, so if your ram needs 2.1 like mine, add whats needed and you should be fine, if still no, lower the timings slightly, example: 4-4-4-15 --> 5-5-5-18
But thats "only" if you experience the restarts or crashes.