depends on the quality of the movie
That's correct. Your output dimensions, frame rate and bitrate help determine your file size and quality of your video. Having a 3:2 format source file is ideal. At 480x320 at 29.97 with a bitrate of 1000kbs+ your video will fit perfectly, look great and be around 300MB per hour. However, if you have 4:3 or 16:9 source you might want to bump up the dimensions of your output file so that'll fill your screen without letterboxing or side bars. In that case, your video file size may go up an extra 100+MB per hour. Video will always look better scaled down than scaled up.
I also don't recommend for quality purposes using any technique encoding a compressed file as mentioned in a previous post. Encode straight from the source (ripped VOBs for an example).