...my dvd player but how about mkv? mkv isn't supported by my dvd player nor my PS3

what's the best format i should convert the mkv to ? forget about the ps3 i want the best format that will hold the quality of the video and the sound for my surround system ??

and since the formats are just containers as everybody say , why don't they use the avi ? why is it the mkv in all the blu ray movies ?