Includes some Disney titles and new stuff. I was surprised that nobody seems to have mentioned it yet. The Disney titles aren't the really popular ones, but there's a lot of A- grade stuff (although there is some definitely B grade stuff too).
Doesn't seem to stack with the 20% off deal since this one is a combo price (and it's cheaper anyway), but keep in mind that it'll be $3 of shipping as it's still 3 items.
I found some arguably decent newer titles like Frankenweenie (2012) and Snow White (2013), plus a good selection of older classics ranging from Ferris Bueller to Mr Bean's Holiday to Mulan. But if you've recently found a burning desire to acquire a tonne of Spongeboob DVDs, then you're really in for a treat.
I added three to the cart and it stacked with the 20% off fine. I'm getting $16.00 for three titles.