Baffling Vista Installation problem

Hey, I'm building my first pc, and the assembly seems to have gone fine but i'm having problems with installing vista. when i switch on, the computer seem to recognise the dvd, and i get to see the words "microsoft corporation" and a loading bar, after this (about 5 secs) a green windows-ish backgorund appears and the mouse cursor, which will move, but there it stays. there is nothing to click or anything, and stays like that indefinitely. its wrecking my head!

Mobo is an Asustek MSn-X AM2 nforce520, and using a SATA DVD RW, vista 64bit oem home basic

there are no instructions, error messages, just a background. what could be causing this?

I Just had this problem as well, although it was with an IDE DVD drive. I was getting hung up at the same place. I would eject the dvd and re-insert and it would come to the country/language screen and then I would start the install and it would say CD/DVD needs a driver. I beleive it is a firmware update that it needs (at least that is what MS support thought it was). They ended up telling me to install it on my second HDD through booting into XP (I wanted to dual boot anyway) and it installed without issue. Hope this helps, if you havent figured out the problem already.