since a windows virus is by definition a virus that affect windows, it's not going to affect your mac files even if it gets access to them.
to rip DVDs i use RipIt and then DVD2one on the rare occasions i want to burn them to disc. generally i just leave them on a hard drive in uncompressed .dvdmedia format, then play them back via an appleTV or Mac mini attached to the TV.
handbrake does this as well for free, but RipIt such a fast and simple program, i use it in preference, even if i did have to buy it.
alternatively, consider converting them to the increasingly popular .mkv format with MakeMKV (free) or handbrake. you won't be able to play them back on a DVD player though. well, not most of them anyway.
to rip DVDs i use RipIt and then DVD2one on the rare occasions i want to burn them to disc. generally i just leave them on a hard drive in uncompressed .dvdmedia format, then play them back via an appleTV or Mac mini attached to the TV.
handbrake does this as well for free, but RipIt such a fast and simple program, i use it in preference, even if i did have to buy it.
alternatively, consider converting them to the increasingly popular .mkv format with MakeMKV (free) or handbrake. you won't be able to play them back on a DVD player though. well, not most of them anyway.