I agree with some of the other moms about going back to some of the "classics". My kids absolutely loved watching shows I watched as a kid, even the ones in black and white. My son absolutely loved the Andy Griffith Show. I even bought him DVD's of it. My daughter loved "I Love Lucy".
Little House on the Prairie
Leave it to Beaver
The Munsters
The Adams Family
Bewitched
The Dick Van Dyke Show
Mr. Ed
Green Acres
The Beverly Hillbillies
Some Nickelodeon shows my kids liked are:
Doug
Pete, Pete, and Pete
Hey, Arnold!
I don't know what's available on Netflix or Hulu, but you've received some great suggestions!