Could someone give me advice on converting some video formats in order to play some movies on an Archos 404.

I need to be able to:

  • Merge an .AVI and an .SRT file into a single .AVI file (or some other kind of commonly playable video format).

  • Change an .MKV file into an .AVI file (or some other kind of commonly playable video format)

Is there a free program out there that does all this?