I just want to add a little bit of background information as to why Norton 360 scans media that may be in your bin. Specially crafted AVI and WAV files can be used to exploit vulnerabilities in DirectX and DirectShow and compromise a system through remote code execution.
http://www.symantec.com/business/sec...jsp?asid=22695
http://www.symantec.com/business/sec...jsp?asid=21527
If you have large media files, all the disk I/O required to scan the entire files will quickly add up. If you created the files yourself (they came from your own camera(s)), then you could exclude these files from scanning, but if you work with files from outside sources (the Internet or third parties), you shouldn't necessarily trust them.