When converting a video to download and play it on any PC, which format should I use?
AVI is the most used globally, but if you want good quality and okay in size, use MP4, AVI today is mostly used by PS3 and PSP users
Agreed with WeirdKid. MP4 is great. MKV is also good, in fact probably better than MP4, but currently there is not alot of hardware support for that format.