For both dvd movie backups and ps2 backups dvd-r is the way to go. Most ps2's don't play dvd+r very well if at all and dvd-r is supported by twice as many dvd players than dvd+r. You can check
here to see what types of media your dvd player supports. The 104/A04 write cd-r, cd-rw, dvd-r, and dvd-rw. The A05(comes out in a few days) does the same except faster. The new Sony Dru500A is the only burner able to write both -r and +r. Pioneer is widely used by users in this forum and is highly recommended.