Oh my goodness, we had a couple of those. I thought I had imagined or mis-remembered it because it's a long time ago now. Some of them were really dark and messed up. I can remember one of the tapes being what felt like hours long, but maybe that's just because of how your perception of time is skewed as a child?
Yeah, the tapes were at least two hours long, I think. Possibly more than that. The ones I watched were old Disney cartoons, so they weren't dark and messed up. They were hilarious to me as a child and I've watched short clips of them here and there since then and they still hold up. Not something I'd watch as an adult for fun, but the quality is evident and I show them to my own kids, especially over some of the contemporary crapola that's made for children in current year. Not messed up, but this definitely wouldn't fly in current year, in one of the Chip and Dale/Donald Duck cartoons, they end up blowing a giant hole in the ground towards the end. The chipmunks listen to voices coming from the hole, as evidently the hole was so deep it went all the way to China. The Chinese voices sound like gibberish, it was hilarious.
Here it is. Donald Duck blew himself all the way to China:
One of them in particular that I remember had Mickey Mouse fighting with a little tornado, and towards the end, the little tornado gets pissed and the big mama tornado comes after Mickey. Another one had Chip and Dale on a farm, eating farmer Donald Duck's apples, to which he gets pissed at and nearly destroys the entire farm trying to kill the two chipmunks. Just good, quality classics, and since it's Disney, the animation is top notch. That's probably what confused us as children, the fact that the cartoons looked so good. We were used to old movies with old timey special effects that couldn't compare to newer movies, so having cartoons look that good tricked us into thinking they were contemporary.
About perceptions being skewed as children: Not my perception of time, but I must've had a dream as a child where the cartoons I was watching went on for longer after the original endings. For instance, I remember seeing longer versions of the Disney cartoons that I watched all the time, that still had another 15-20 minutes after the normal endings. I had convinced myself that these were special cuts of the original cartoons that went on for longer. I had myself believing this for a long time, but have come to realize that I must've dreamed this whole thing up.