can't move video and pix files back to iPod Touch from desktop computer

I moved (via drag-and-drop in Windows) video and picture files from an iPod Touch (iOS 5.1.1) to a Windows 7 desktop computer. I want to copy some of them back, but it won't let me drag-and-drop to copy them back to the iPod. How do I get the files back on the iPod? I know that the "disk mode" is not available on the Touch. Also, although the iPod shows up in iTunes on my desktop computer, these video and picture files (Quick Time Movies, JPEGs, etc.) don't show up there. So, I'm out of ideas. A related question: how do I scan the iPod using my Windows 7 desktop computer's anti-virus application (McAfee)? Normally, when I right-click on a device on the desktop computer, it offers me the ability to scan it for viruses. Not only does it not give me this option for the iPod; the iPod doesn't even show up as a hard drive; it shows up in the window as a separate "flavor" of drive. Is there a way to make Windows 7 think that the iPod Touch is just another USB-connected drive; i.e., is there a way to mimic the disk mode option that is available on other models of the iPod other than the Touch?