DVDShrink beats other software hands down if you want to rip and reencode DVDs. Before the DVDShrink days I had to rip using SmartRIP, and then encode seperatly using mpegrecode. The whole proccess used to take a good 10 hours, not to mention the mess manually editing DVD nfo files, etc. With DVDShrink you stick your disk in the player, and it transcodes it as it is being ripped, giving you a nice 4.3GB folder ready for burning with nero
If you want to download DivX's and burn them to DVDs, the easiest option would be to use NeroVision to do it all for you.
As to the best media to use, I would advise you experiment. Buy a few types of disks, and see which work on your intended player. From the ones that do work, go for the cheapest.
There is no difference as such in the proceedure for writing to DVD+/-R(W). I can get DVD-Rs for 45p or so on a good day, but they do not work with my ancient stand-alone player. DVD+RW's cost me £1.25, work perfectly on my player, and have the bonus of being reusable. Other people have players which will read almost anything. Your milage may vary. Buy a few discs, and see what happens.