Some programs are affected by sp2 but not to many.
I would suggest you run sfc.exe /scannow
http://support.microsoft.com/default...b;en-us;310747
this utility will check windows xp.
There was problem in the past with windows explorer and IE
they where taking to may cpu cycles thus stalling. Usually one can check the
cpu cycles taken by ie or we in the task manager.
One utility I use for monitoring what goes on my computer is process
explorer from sysinternals
http://www.sysinternals.com/ntw2k/fr.../procexp.shtml
it's a bit technical but it will show you what goes on.
Error oir problems can sometimes show up in the event viewer.
%SystemRoot%\system32\eventvwr.msc /s