For the nth time in the past couple weeks, I encountered a PC with Norton installed (this time as part of the Verizon/Yahoo apps) that slowed down the computer and failed to uninstall. The only remedy was to go to the Symantec website and download their Norton Removal Tool. Their normal uninstall process was running for an hour before I just decided to kill it. In the past couple weeks I've seen this same problem happen on Norton 2006, Norton 2007 and Norton 360. And I remember seeing this a few years ago on Norton 2003 and Norton 2004. So in the last 5 years, they still haven't fixed the problem.
Here's the link to their removal tool for those who may need it --- service1.symantec.com/SUPPORT/tsgeninfo.nsf/docid/2005033108162039.
My advice to anyone running Norton, remove it (if you can) and switch to AVG (free.grisoft.com). AVG doesn't slow down your computer and it uninstalls in about 2 minutes.
If you need anti-spyware, use Microsoft's Windows Defender (www.microsoft.com/athome/security/spyware/software/default.mspx) and just stick with the Windows firewall (on XP and Vista) instead of installing 3rd party firewall that Norton and McAfee will try to sell you. If you have a wireless router, you're already protected by a hardware firewall in the first place, so between that and the Windows firewall, you're pretty well protected.