Personnaly I would avoid an All In One solution as they can cause problems.
Also sometimes it is better to use more than one scanner as they detect things in different ways.
To make sure everything is running fine run both anti virus and anti spyware apps in normal AND safe modes. (make sure that they are updated first ! ;)) (AVG (http://free.grisoft.com/doc/1) is good and free AV)
(A couple of good removal tools are Spybot (http://www.safer-networking.org/) and Adaware (http://www.lavasoftusa.com/software/adaware/))
ALso an on line virus and spyware scanner is Trend Housecall (http://housecall.trendmicro.com/)
Just a note: actively running two AV's on one machine can cause problems.
So if you are thinking about it make sure your current one is disabled first.
Same thing applies to online scanners as well.
Removal of junk files is easy with CCleaner (http://www.ccleaner.com) a free app that does exactly what that.