Thanks for the updates.
Looks like the failed installs have changed settings. Ignore previous instructions and see if you can get a responsive system.
If you have a recovery CD, use it and select system restore to go back to before the failed installs.
If no disc, start in safe mode with Command Prompt, type rstrui.exe
FYI. you cannot undo a system restore when using command prompt, but you can choose another one if available.
If the system is stable enough, back up your Data.