I was, and still am, a big fan of Gummi Bears, and own the first three seasons on DVD. When my nieces and nephew come over to visit, that's what they want to watch. None of this sponge bob nonsense in my house.
All of the old Looney Toons, I've got 100's of em on DVD, they never get old.
I really liked Cat-Dog and Hey Arnold too. My kids watched Rugrats when they were younger, and after awhile, I sorta started liking that too.