Use MeGUI. It’s had very little work done on it in the last year, but it’s considered x264s best interface.
It’s rather difficult getting a hang of at first, so if you need any advice, feel free to email me about anything: korochko@hotmail.co.uk
Oh and by the way, I was able to compress 1920×800 and 1920×816 videos ripped from my own BluRays from 33GB and 24GB to 4GB and 6GB respectively. And I’ll tell you what, the quality is outstanding.
H264 is a bad compressor, yes. But with x264, you should be able to get files down to tiny file sizes. (40-80GB = lolerz!)
Fair enough if that’s an uncompressed AVI, but after compress…no. 🙂