Lost Sign in page with XP

I have lost the page after the Welcome screen where you select account icons
or pictures. I have lost the sound going from the Welcome screen to the
account screen. I get the Welcome screen and the go directly to my desktop.
I am using Windows Home XP Service Pack 2 and all the lates updates from MS.
One thing I did was install Norton Antivirus 2005. On boot up I get the
error message: Norton Antivirus 2005 does not support the repair feature,
please uninstall and reinstall. I taken Norton out and put it back and took
it out again now it is out but I still have the problem of the Account
screen. Can anyone help me get back to normal?