I'm wondering which video format is best if one wants to encode some videos. My friend has got me to convert .rmvb files to vcd (.mpg) format. However, I've noticed that the .rmvb files were like 70mb and once converted to .mpg they were like 250+mb big. Can anyone suggest the most suitable file format that gives good compression, while retaining excellent picture quality? I'm about to experiment on .rmvb and .mp4 formats (for myself) to see what the qualities are like. Haven't had a chance to check these formats out until now.