I installed service pack 1 to my Windows XP Pro the other day. Now it takes 5 minutes to open outlook express. It was also forcing me to use Windows messenger and found a mail.com e-mail address I have to sign me in ( I did not give it the address), but today I haven't seen the messenger icon at all - like it's not even installed. I don't really care I don't use it but it worries me that something isn't right.
Also the computer won't go into standby because of the TV tuner driver. I never had the problem previously. If you haven't installed the service pack yet, definitely have the installer create a backup so you can uninstall it if you need to, it gives you the option.
If I was the only one using this computer I don't think I would even bother with Windows.