The CWShredder program hasn't been updated since May. I thought that I had read somewhere that the folks behind this tool finally gave up trying to keep up with all the variants of Cool Web Search. No harm in running the tool, but don't be lulled into a belief that CWS will be completely removed from your system by running this program.
If your system continues to exhibit strange behaviour, you may have to look for Spybot S&D on the web to analyze your system and look for additional incarnations of CWS (and other spyware nasties).
It's a dangerous place out there. Microsoft just released a patch to close another security hole in Windows. Our IT department just sent out an urgent message to all employees to do a Windows Update immediately. If you haven't patched Windows recently, I might also suggest that you take the time to download the security patches. One way to do this is to click on the "Tools" tab in Internet Explorer and select the Windows Update option.