Would be a great feature, I don't see it as a option in settings, just in iTunes itself however I think it is mean't to work the other way around by allowing the computer to serve the iDevices content.
Not to be rude, but a couple things wrong with your post.
2) Windows isn't based on DOS, originally ran on top of DOS, hasn't done that for a long time!
A) Mac's can and have gotten viruses
3) Both Mac & Windows have built in firewall
To the OP, I would recommend Zone Alarm, one of my favorite...
Ugh, IMO Glasses free 3D sucks, it's fun to look at for a minute but that's about it, hard on the eyes. Funny thing is having the 3D video camera that is good for shooting 3D Videos that "only" work on your phone, no thanks!