Jeez this thread makes me feel old...
When I was a kid, I remember my brother and I getting up early for
Scooby Doo,
JabberJaw,
Speed Buggy (which all three shows are actually clones of each other), and when it came out, the
Harlem Globetrotters. Of course
Loony Toons was always a favorite as well. But the real family treat was the reruns of the original Jonny Quest. Oh and while it wasn't a cartoon, the Little Rascals and the Three Stooges always brought a smile to my face, they still do.
As for recent ones, I enjoyed the hell out of Avatar and I'm finding myself also enjoying the Clone Wars as well.