First of all, don’t ever do “make movie.” In After Effects you should pretty much always render files using the render queue (Composition>Add To Rendere Queue). It offers way more control and way more options, including h.264. Once you add the composition to the render queue, you will need to set options in several different places, but focus on the “output module” section – this defines the type of file you want to output. If you set it to Quicktime format, you will be presented with all the codec choices available on your machine, including h.264.
That said, After Effects really isn’t so hot at rendering out compressed files, never has been. It will work, but the files are almost always larger and of lower quality than you will get with Quicktime Pro or any other third party application. Quicktime Pro is great for outputting any Quicktime-based formats, and worth every penny. There are free compression programs available though, such as Super C, that will get the job done quite well. You just have to poke around on their site a bit to find the download link, they move it around to keep people from hotlinking directly to the file. It’s a good little app that I’ve used quite a bit so I can vouch for it.
Brendan Coots
Splitvision Digital
http://www.splitvisiondigital.com