I hadn't heard of this "stuffed in the fridge" term before (though I have heard "nuked the fridge" from the "Indiana Jones and the Kingdom of the Crystal Skull" movie- essentially meaning the same as "Jumped the shark" in TV shows. (and I don't care for either term really- because both Indiana Jones and Happy Days have always been cool with me. )
Anyway- good choices you have here. I can definitely agree with Starscream and Cobra Commander- though he didn't technically die in "G.I. Joe: The Movie", did he? I thought the deal was that he literally got turned into a snake and slithered off.
As to Krang and Shredder, I can't say for sure as I haven't seen those episodes of Teenage Mutant Ninja Turtles yet. (Or at least if I have, it was back in 1995 or 1996 or so- and I can't recall them right now.) I really wish Lionsgate would release the last 2 seasons of the '80s cartoon on DVD so I could have the whole set. I've been watching the entire series in order on DVD since they started releasing the show. (Though they did leave out a few episodes for some reason, but I've been able to obtain those episodes as well- looks like they were released to VHS back in the day, but couldn't be put on the DVD for some reason.)
Jaga was pretty quickly taken out of the picture on ThunderCats, if that counts. But then, he did a Obi-Wan Kenobi deal and became the ghostly advisor for Lion-O, so I guess his character didn't really go away necessarily.
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