NB: WinXP SP2 is considered a Critical Security Update (your "security
patch")...but I wouldn't install it just yet. See below.
Running WinXP SP1, I would advise you to install all nine (9) of the Oct-05
updates. Though only three (3) are considered critical (MS05-050, MS05-051,
MS05-052), the others address important security vulnerabilities, Ellen.
Furthermore, I suggest you enable & use Automatic Updates to make certain
your machine is always fully patched:
How to configure and use Automatic Updates in Windows XP:
http://support.microsoft.com/?kbid=306525
Now, back to your problems. If uninstalling 'Security Update for Windows
XP - 896688' via Add/Remove Programs & rebooting does fix your problem, I
would suspect that the Malicious Software Removal Tool (your "patch for
removing bad software") removed some "hijackware" and either some "bad guys"
remain or the removed "bad guys" broke something. You need to check for
more "hijackware":
Checking for/Help with Hijackware
http://aumha.org/a/parasite.htm
http://aumha.org/a/quickfix.htm
http://aumha.net/viewtopic.php?t=5878
http://mvps.org/winhelp2002/unwanted.htm
http://inetexplorer.mvps.org/data/prevention.htm
http://inetexplorer.mvps.org/archive/tshoot.html
http://www.mvps.org/sramesh2k/Malware_Defence.htm
http://defendingyourmachine.blogspot.com/
When all else fails, HijackThis v1.99.1
(
http://aumha.net/downloads/hijackthis.zip) is the preferred tool to use.
It will help you to both identify and remove any hijackware/spyware. **Post
your log to
http://forums.spywareinfo.com/,
http://castlecops.com/forum67.html or
http://aumha.net/viewforum.php?f=30
(where I'm a moderator) for expert analysis, not here.**
Once everything's hunky-dory (and I want the opinion of a HijackThis log
expert before assuming so), then you should immediately go to Windows Update
and install WinXP SP2. After reboot, return to Windows Update and install
all critical updates offered you.