The Simpsons is an incredibly popular TV series which has been available for decades and it is currently running in its 25th season of something. Are you looking for something to watch tonight? Why not watch The Simpsons?
You can buy the different Simpsons seasons on Amazon.com on DVD, Blu-Ray or maybe as an Instant Video if you want to watch right away.
The Simpsons is probably not the show that you want to show small children coming over for the weekend, because even though this looks and feels like a children program, it is kind of more for adults as it is having fun with popular persons, making fun of people and it also has lots of political jokes. If you would rather want to watch a TV series more suitable for children, then I would for sure go for Little Einsteins instead.
Have fun watching The Simpsons and do not forget that you will need quite some weeks if you want to watch all 27 seasons!