Newb Q: "J.S.Downloader-AQlt (Trj)"

My old XP was acting slow so I did the full scan and it came up with the above file in “C;\Docs+Settings\owner\Local settings\App…”
Then it recommended running another scan at boot-up and I clicked that and it rebooted my computer and scanned again.It then found the file again and I had choices including “3;send to vault” (or whatever) yet nothing happened when I clicked this option. So I clicked “escape-3” (I think it said) and got a notice “scan aborted”.
I’m confused because the scan seemed to be finished. I looked in the vault and it is there.
Q-1; Am I now safe or do I need to do something else?
Q-2: Should I just delete it?
-3: How did it get in and is it a particularly evil or difficult virus?
Much thanks in advance! BrianAlex

Q1 - check your computer for malware with Malwarebytes

Q2 - let it stay there for a couple of weeks before you do
( Clean, Quarantine, or Delete? http://antivirus.about.com/b/2007/03/11/clean-quarantine-or-delete.htm )

Q3 - probably from infected website http://www.symantec.com/security_response/writeup.jsp?docid=2003-102718-1528-99

Check your computer for malware with this

Malwarebytes Anti-Malware 1.50.1 http://filehippo.com/download_malwarebytes_anti_malware/
always update so you have the latest signatures before you scan
click on the remove selected button to quarantine anything found

post the scan log here

Means…??
SP…??

Thanks Pondus. I did scan with my updated “Superantispyware” and it just came up with the usual cookies.
I will wait a couple weeks and maybe delete it. I also feel like deleting my resore points in the near future if there aren’t any problems.

Asyn: I meant to communicate that the O.S. was an old version of XP, as in Windows XP.Sorry.

I know, I want to know which SP is installed…??

Oh,got it! (Duhhhh) Sorry,It’s SP3 all up to date. Thanks.BA