Two imports (from Germany, imported through orgazmik.com):

Both DVD, region 0, PAL video format (require PAL/NTSC capable DVD-player, or virtually any DVD-ROM drive).

Title 1: Das Mädchen-Internat (roughly - The Girls School) [Featuring Kelly Trump]
Title 2: Gina Wild - Durchgefickt - jetzt wird's schmutzig 4 (thorougly fucked - now it's getting dirty #4)

Casts - unavailable on packaging except for the two 'stars'

#1 is a straightforward story, scandal in a girl's school, lots of sex, all in German. Printed runtime of 100 minutes (or 1:40).
#2 features a branching story - you can move around through different scenes. There's also a little bit of advertising, but it can be safely skipped. Behind the scenes shows some still images with several of the sex scenes in the background. There's also a featurette featuring Gina, but mostly just going through poses and some brief interviews. Again, virtually all in German (except for the one Swedish accent who can't speak a word of German, and thus communicates to the others in English).

Ratings - #1 - okay, good for a couple of views.
#2 might be worth a couple more viewings than #1, for the featurette and to make sure you got through every branch of the feature.
Knowledge of German not really necessary for either, though it never hurts.