What is a good DVD burning application for Windows XP that can create an disk that is mountable on Mac OSX? Of course, free would be nice.
Have you checked out CDBurnerXP?
Incidentally, I'm pretty sure OSX will open any Windows DVD format so you shouldn't need to do anything special. At least I've never has a problem. I believe there are issues going the other way, OSX->Windows, if you use HFS+.
Mountable? How about Free DVD ISO Maker:
Then in OS X Terminal:
hdiutil mount /path/to/file.iso
Macdrive. I've used it before.. Its a nice solution, however, its is not free.
Simple and easy to use, MacDrive is a must-have utility for anyone working in a Mac and PC World.
MacDrive gives you hassle-free, seamless access to Mac files on Mac disks directly from Windows. You can open, edit and save files on Mac disks, as well as create new disks and repair damaged ones. MacDrive is like having a Mac interpreter in your PC.
MagicISO is not free but it is very full-featured:
MagicISO is a powerful CD/DVD image file creating/editing/extracting tool. It can open / create / edit /extract CD/DVD image files, and it can convert bin to iso and back. as well as make ISO file from DVD/CD-ROM or hard disk, and handle bootable information at meanwhile.