I was checking out a music forum when out of nowhere I get a message from my AntiVir virus checker. ''TR/Spy.Banker.vk.1'' so I quickly put it in my quarantine. What should I do now? Do I delete it from my quarantine or do I need to do other stuff to safely remove this?

Keep it in quarantine for now, as long as it is in there you should be safe. Don't visit any sites on that pc that require sensitive information (passwords or any banking sites). To be sure your pc is not being affected by any malware do a couple of free online virus scans: http://housecall.trendmicro.com/ http://www.bitdefender.com/scan8/ie... http://www.pandasecurity.com/homeus... Also you can try a variety of free spyware / adware removal programs if you wish such as adaware or spybot search and destroy. If after a week or so your pc isn't affected by the quarantined file(s) they should be alright to delete from the av quarantine. After this is done run your virus scan again just to be sure.

Why not to delete it?

If the malicious script the antivirus scan has picked up infected a system file, you might not notice right away. If error messages start popping up during startup or when you try to run particular programs you might find the error message relates to a quarantined file. This way you have the option of repairing the error while you still have the file. There are sites that you can upload the file(s) for scan and repair if you find this is the case. Basically it pays to be sure you have system stability before deleting anything if you are not completely sure it is fine to do so.