Repair Computer does nothing.

Hello,

I've been trying to reinstall windows as my Inspiron 1545 (Vista) is laden with programs that are slowing it down. On start up, I hit the F8 Key and get into Advanced boot options, I then select 'Repair your computer' but nothing happens, it just boots normally. I have a recovery partition with the factory.wim file along with other files and folders. I tried running PCRestore from the recovery partition but always get a blank error after a few minutes. There is no Datasafe folder on my laptop either. Trying to boot from the recovery partition fails has not been possible as I don't see that partition as a bootable option in the boot option menu. Ctrl+F11 seems to do nothing either. Would it be safe to mark it as an active drive?. I also don't have any recovery CDs. I tried using ImageX to load up the factory.wim file but ImageX closes immediately after opening it and running it from the command prompt doesn't work: It says ImageX is not a recognised operable batch file.... I don't think I can make a PE disk as the Inspiron only has 3GB of RAM while the .wim file is over 5GB.

Any help would be appreciated.

Thanks.