The Price is Right:
How to make a cartoon easily.
1) Get a multiplayer game engine with a level builder like Minecraft.
Minecraft allows you to build a world without interference from the mobs ("creative mode").
2) Build a virtual movie set in the game environment.
It also allows you to make skins for the players so they can look more or less how you want.
3) Make player skins with a graphics program like Photoshop or Gimp.
4) Record a multiplayer game with a screen recorder like Fraps.
5) Get a conversation tool like Skype or Teamspeak and record the script dialog during a live game session in the set you made. Have your friends play your characters!
6) Use a Video editing tool like VLC to downmix the audio and video recordings to a single file.
7) Upload the file to a video hosting site like Youtube.