Well Arnel...not all conversion programs include a burning feature. DVD Santa does but some programs that I use like AVI2DVD (which rules and it's freeware so you never have to pay for it) don't. They're simply tools to help you convert and build a DVD. Change avi/ogm/mpeg/etc. files to MPEG2 DVD files, add subs, add menus and the like. AVI2DVD takes up quite a bit of space when converting files though since it makes both .iso AND .vob folders and also stores the converted video and audio in a folder. All told one project can take up 12GB.
Maybe it won't if you make some changes...haven't messed with it too much yet.
DVD Decrypter is important since it will decrypt copyright protection. Suprisingly, it's pretty rare that a company will allow you to copy such discs when they advertise that they'll back up your DVD collection. Haven't tried a copy protected disc with DVD Santa so I don't know if it'll work around that.
On a side note, I'm about ready to forget about DVD Santa. It was so glitchy I emailed XY Software (the makers of the program). That was 4 days ago. Glitchy products combined with sub par technical support is just shitty. If I don't hear anything by Monday, fuck 'em. I really liked the program, too. I probably would've bought it if it had worked right or if someone had to told me what the problem was.