tiserv.32? please help

yesterday i was browsing around on the internet and i tried to download this file (stupid me, i didn't even think twice) and norton 2009 said it detected backdoor.tiserv.32, I think that's what it is. anyway my computer froze up so i shut it down and when i restarted it this screen came up and said that a error has a occured and windows needed to shut down. so i restarted it again.
and everything's working fine, there are no visible problems, nothing's moving slow, except when i ran a fall system norton scan it was over than less in a minute. those things usually take 45-60 minutes, i know because i am always frustrated with it. and when i searched the name of the virus on google it didn't take me to the page, even one time it redirected me to "no more surfing.net." From the description of the virus i am assuming that it indeed infected my computer. i'd just like to get rid of it (It's on my Windows XP 2003 PC) because i want to plug in my zune to update music but i also heard that it infects removable drives or something, and my zune is not even a day old.
if anyone knows the real name of the virus (because i'm sure I got it wrong), pleas please PLEASE respond. and im somewhat computer literate, but when i read the instructions on how to remove it it said to delete all this registry stuff (???) so if you guys could just direct me to a excellent malware/virus remover it would be greatly appreciated. thanks

Please download the current version of HijackThis from HERE

• Double click and run the installer.
  
• It will install to C:\Program Files\Trend Micro\HijackThis\hijackthis.exe
  
• After installing, you should get the user agreement, press accept and Hijack This will run.
  
• Select Do a system scan and save a log file. This will open a notepad file of everything Hijack This found, copy and paste it back here.