So, you want to make your own cartoons, it can be tough, but I'll show you what you need. ;)
For animation, you should use Adobe Flash Pro CS5.5 [Old Version]. It can be really good for animation, but the learning curve can be steep and there can be problems depending on the version you use. But it's my favorite.
For editing, I recommend Sony Vegas Movie Studio 9 [OLD VERSION] for PC users, and iMovie for Mac users (Because Final Cut is very unsuitable for animation, trust me). Sony Vegas provides all the tools you need to edit and upload your movie to YouTube all other websites. iMovie comes free with every Mac, but I recommend upgrading to iMovie '11 if you don't have it!