Boot up problem

[dodgeyblade]

Hi all.Running Vista home premium
Daughters laptop was running very slow,so I decided to clear a few things off to see if it would clear it enough to be reasonable.I read on one site to disable the UAC to get rid of the black screen that keeps coming up.I did this ,but re-enabled it.I then used eusing free registry cleaner.I turned it off then back on and now it's stuck in a bootup loop.It can get past the original page then goes to the error recovery page.I've tried normal startup and last good configuration startup.Then it goes to the black screen with microsoft corporation on it and it starts to load then a blue screen with some words on it quickly flicks on and off then it restarts and keeps doing this.I've tried a recovery disc from bootup (one i downloaded not original),but no joy.
Any suggestions ?
Thanx in advance

[not important]

Try the Vista Recovery Disc. http://www.pcworld.com/downloads/fil...scription.html