help! vista won't load

Hello everyone

I have Vista business installed on my toshiba laptop' and it won't load.
when i try to start my computer, i reach a screen that says windows could not start, and that i should either try to restart it normally (leads to notorious blue screen) or try to use windows repair. the repair option leads me to a grey screen that says the program could not load and the computer will shut down. there is no option to reach system restore or the vista recovery tool. i've tried to use my recovery disc that came with the laptop, but it attempts to format my drive and reinstall windows and does not offer to restore my previous settings. I really can't afford to format my drives right now!
important data that might be relevant: I've done 2 foolish mistakes apparently: the first was to use TuneUp utilities to optimize my vista. the second was to uninstall a driver called something 4to6 that is related to my network adapter. i was trying to uninstall and reinstall it, and in between i restarted my computer, and that when trouble began. i don't if this could be related. the funny thing is that even after optimization and uninstallation of said driver, everything seemed to be working just fine.
I was aware enough to create a restore point before all these changes took place.
any idea on how i can reach it/restore my system?

many many thanks
roy