Windows 7 registry/drivers problem  

I wanted to clean my computer using some quite complex program with many functions as registry problem fixing and driver problem fixing. So I started a scan. Result was about 500 problems to fix. I decided to use backup option before choosing to fix. So after backup and fix, program demanded restart. All loading was fine but when came to load desktop, it did nothing. Just black screen with no response. So i restarted and used safe mode. It started to write out drivers and then it stopped on "classpnp.sys" and again jumped in black. Can anyone help how to restore system? Even tried Linux (SLAX) but even with some "Windows modification" program didn't run.

   Information

Boot up using the Startup Repair CD or Windows 7 DVD. (not the OEM manufacturer's Recovery Disk) If you have a Netbook, you will need a CD/DVD drive.
NOTE: Make sure no USB drives are plugged in.
Do not use a USB Pendrive for Startup Repair.

Try a Restore point, before your playing about.
System Restore
System Recovery Options

   Information

We always assume you have made your Recovery Disks using the OEM manufacturer's app the first day you had your new PC.
& made the Startup Repair CD.

For better help with problems, Can you post your specs.
Filling out System Specs
System Info - See Your System Specs

Dont Know What Hardware You Have..??
VistaForums SysInfo Tool - Vista Forums

Thanks for your reply.
I tried one restore point but no changes. Problem is I dont have recovery disk. None was there when i bought notebook. I read somewhere that Acer notebooks dont use recovery disk, but there is hidden part, that can be "somehow" used during computer start.

At the acer screen on bootup, press Alt-F10 (hold down both keys together). Then follow the prompts.

I chose option to find and fix problems during start-up. Now its about 7 hours and its still working with no sign of progress. Is that normal or should I try another way?