Apple's own DVD-R disks work the best (available in the Apple online store in both 4x and 8x speed), but I find that Verbatim media also works well with my SuperDrive. Maxell/Memorex seem to be the least reliable on my machine.
Of course, as with anything else, your experience may vary, and it's impossible for anyone but yourself to figure out which media works the best. We can only recommend what works best with our systems, but even someone with an identically-spec'ed machine as yours can still experience very different things with identical media.
Verbatim dvd's are the best I have used. I have burnt a lot of dvd's on various macs and pc's and only ever had one verbatim unreadable dvd.
I can't say that for any other brand that I have used and I now use verbatim exclusively unless forced to use another brand.
(never use Sony discs, you'll end up throwing half of them in the bin, dreadful!)