Best file format for Movie Library?

I'd like to move my movie library to my PC, I have a 360 and PS3 to stream them to, and also an ipod, psp, and blackberry storm. Any suggestions on what the best format to store my library in to be able to watch on the most devices but still have good quality? I was thinking mp4, but would the quality be good when streaming to the TV?

Thanks in advance for any suggestions!