Your SuperDrive doesn't do DVD-RAM, which is essentially a high-capacity phase-change optical disk. It's not really a DVD in any sense except for the size, and most DVD players and DVD-ROM drives cannot read them. Think of DVD-RAM as a huge zip drive.
Burning a DVD is like burning a CD, except that it holds more.
In OS X, you can burn data DVDs from the Finder, just like data CDs. But, of course, Toast is nicer.
Apple's media is the cheapest name-brand blank DVD media you can get. If you go with off-brand, be prepared to test a couple of brands to see which ones do and don't work with your drive (and beware that media vendors may change suppliers at any time, negating your research efforts).
tooki