Oh Boy!!!! oh Boy!!!!
I get to say I told you so again and again and again over and over!

1) Learn how to back up your system!

2) If you don't know what to do...don't do anything!

3)Learn how to google for information on programs and services and files that are installed....that way if it needs to be uninstalled you learn how to properly uninstall the program or application. Some programs require that they be uninstalled with their own uninstaller package....doing anything else causes "fatal errors"

**************ok that said*********************

Try "system restore" this is the first line to restoring a computer after a bad download or uninstallation program

Open System Restore by clicking the Start button , clicking All Programs, clicking Accessories, clicking System Tools, and then clicking System Restore.* If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
Then pick a restore date previous to the date of the error..(usually only dates in BOLD font are restore dates.)

You can also visit windows up date and get the netframework re-installed.

Do this first and then see what is left to work on!