Those are usually just changes that Spybot noticed that YOU probably made yourself such as allowing your own antivirus program notify you instead of Window if there is a problem with it. If that is the case, then you can right click and exclude that detection from future scans. This link from the Spybot forum will explain this better than I can. Start with the second post (Spybot Sandra's) and read down from there.

http://forums.spybot.info/showthread.php?t=75