Well you should no that Norton products are among the worst out there and have been known to cause problems such as slowing down the computer and blocking random websites. If I were you I would Download the Norton removal tool from here and then get a better Anti-Virus program such as Macafee or AVG.(Links to them in sticky) As for the combination of the programs, since your AV program already has a firewall turn off Ewido's Resident shield. I would shedule Ewido and Spysweeper to switch off scanning. So it would be Ewido one day then Spysweeper the next day. Set them to run at like 5:00 in the morning so that they run when nothing is going on. That should make your computer run a whole lot faster.