Welcome to the forums.
A couple things first... if you're running any AV (antivirus) software, uninstall it. Especially if it's McAfee.
Afterwards, download and run a program called RegSeeker. Run the "Clean Registry" section and remove all the leftover registry entries. The program is easy to use, just extract the contents of the zip file to a folder and run RegSeeker.exe.
If that still didn't bring Add/Remove back, try this:
Go to Start, Run, and type in: REGSVR32 APPWIZ.CPL
Click OK.
Restart your computer.