Having some problems with Kaspersky

Right now I have three questions. The first one is that I just recieved an external casing for an internal hard drive that I have and I am having a bit of trouble with it at the moment. I just hooked everything up and it seems to be running fine but when I scanned the hard drive with Kaspersky it found a couple of files that seemed to be bad.

not found: Trojan program Trojan-Downloader.Win32.Agent.bcw File: C:\System Volume Information\_restore{01E3BB89-199B-4F2D-A1CF-F3151D024D34}\RP430\A0089659.exe/stream/data0009/data0003
not found: Trojan program Trojan-Downloader.Win32.Agent.bcw File: C:\System Volume Information\_restore{01E3BB89-199B-4F2D-A1CF-F3151D024D34}\RP430\A0089659.exe/stream/data0056/data0004
detected: malware not-virus:Hoax.SWF.Alerter.a URL: http://70.86.120.158/xp-cydoor-728.swf
detected: malware Exploit.HTML.Mht (modification) URL: http://www.onlineemedia.com/metist [...] x&uaid=del

Can anyone tell me what not found means? I was under the impression that if an anti virus spotted something that meant that the file was found, I have no idea what not found is suppose to mean.

Secondly, I put the external hard drive next to my mouse and all of a sudden tthe mouse started to move to the bottom right corner of the screen when I wasnt telling it to do so, the problem stopped when I disconnected the mouse and reconnected it but it still worries me that it happened in the first place. My question is, is the hard drive messing with my mouse?

Thirdly, the hard drive that I have hooked up to the external casing was once the main hard drive in one of my old computers and so it has XP installed on it and I was wondering if it would be ok to just delete all the windows folders off of the hard drive now that its just being used as a storage hard drive