Spyware Stop

I bought this software about a year ago. I would use it about every day. After every scan, it was usually the same cookies and not spyware very often. The problem with it is that the files that returned after the scan were unfamiliar names. Some of them, I could tell what website they were from, and some of them I couldn't tell. It was free for the first week or month as a trial version and then I purchased it. Then later I realized that Windows Vista already has spyware software in Windows Defender. Every time I ran Windows Defender, It said that it didn't find malicious software. I'm not sure which software is more reliable. www.SpywareStop.com