I forgot to add that once the login screen appears windows loads quickly and I do not have any performance issues with running games or CAD programs.
My system is rather old (athlon T-Bird 1 Ghz chip, Asus A7V mobo, 1280 megs ram) and I have never had this problem before.
Just recently it will load the black screen with the XP logo and the moving dots at the bottom, then it will switch to a black screen and it takes about 6 minutes for the blue login screen to appear.
This used to take less than 30 seconds. Any help would be greatly appreciated.
I don't believe that I added any new software or changed any settings before this started happening.