Thundercats is one of the best animated programs to emerge in television. Back in the 1980's cartoons tended to be somewhat condesending and insulting to children's intelligence. Thundercats was a refreshing exception to that rule.
Where most shows would have their oligatory moral of the story presented at the end of the show, or slammed into your head during the program, like He-Man, Superfriends, G.I. Joe, etc. Thundercats managed to present gripping morality plays without being obvious about it for the most part.
Add to that the strong Japanese anime influence which was well before anime became the hot commodity it is today, and the wonderful blending of technology, magic, myth, monsters of all sorts, Eastern philosophy and combat, and Western sensibilities and you have great drama.
To top it all off, you have heroes that have character flaws, especially Lion-O in the first season. At a time when most heroes were involate archtypes, Thundercats presented a far more believable and human set of heroes to enjoy.
Yes, the DVD release could be better in terms of quality and special features. The special features are quite sparse and of questionable value, and the quality of the episodes themselves appear to suffer in all likelyhood from poor quality masters in need of restoration. That being said, the sheer joy of seeing these episodes again is well worth the expense even with its flaws.
If you haven't seen this show, you should, whatever age you are. This show proves that animation isn't necessarily just for kids.
Sword of Omens, By the Eye of Thundera, come to my hand!
Thunder, Thunder, Thunder, Thundercats Ho!!!!!!!