Thanks for your help guys, I've sorted it, found this on another site and it worked.
"Relevant answer is here:
Firstly, if you have it set in the bios to boot from the cd/dvdrom it can cause installation to loop after the first reboot, as it restarts installation and loops - to fix you remove the install dvd during reboot, or go into the bios and reset it to boot from the hard drive first - so you need to remove the dvd while its rebooting quickly - you have 15 secs to do so before it restarts if you don't hit a key, or go into the bios, and reset it to boot from the hard drive.
You have to be watching the last part of the install and be ready to pull the DVD out. I also hit the Del key so I could reset the BIOS Boot setting. For all other Win OS I have set CD/DVD to be the first boot device followed by the HD, but of course the Geniuses at Microsoft had to screw this up and create headaches for some of us. Logic and prior experience will not have helped you figure this one out. Keep in mind that it is helpful to assume that MS has done something really dumb. Then you will be on the right track.
I consider this a first class BUG. Will Microsoft pay me for the 8 hrs I wasted trying to solve this ridiculous stupidity? I doubt it.
So, it seems to me that when you install Win7 you must not have DVD as your first BOOT device, and simply hit F12 (on most hardware) in order to get an instant window asking for Boot Device Choice.
What a PITA.
I hope this helps others who have the same problem."