Thanks so much for the help, everyone.
Matth -- So, I guess the issue is that if the buffer (hardware and software) stays filled up, and the burn is never slowed down, then the fact it's dispersed small files is having no effect on the burn. It's reassuring. I'll probably keep an eye out on the first two burns or so (for the buffer levels, as you pointed out), but, yeah, it seems like it should not be a problem.
Kerry56 -- Yes, I actually do have Verbatim AZO 16x. I am aware of Taiyo Yuden too, but have read posts from recent years with people questioning the quality of both the Verbatim AZO's and TY -- with TY I think it may have been workforce cuts associated with the purchase of JVC, and with Verbatim it may have been the discs made in the India plant (though don't remember reading if that was the only issue). I remember that years ago, people seemed to consider TY to have a slight edge. In your opinion, are TY's still as good as before (are they slightly better than Verbatim AZO's)?
Albert -- Thanks, they are divided into folders already, but that's something I hadn't thought of at all. I'll see to make sure if the folders aren't too big.
CDan -- I hadn't thought of that.. at all. It's funny b/c I was in fact using a flash drive for temporary backup myself on a smaller scale, but for my parents' pictures, I had a mind block and thought there must be another way but drew a blank.
Wombler -- Thanks for that as well -- another thing I hadn't thought of. Will try to make it work (a sibling's house).
I realize they might not be as relevant since they're arriving just as people are moving away from optical media, but do you guys feel MDiscs are a good option, or simply too much of an unknown despite the Dept. of Defense tests? (they'd be in addition to regular DVD+R's.)