Plays:
CD
DVD
VCD
SVCD
XVCD
XSVCD
DVCD
SDVCD
XDVCD
XSDVCD (If there is such a thing)
RealMedia
MP3 (including VBR) (any accepted media) (ID3 tags display)
OGG (including VBR) (any accepted media)
WMA (any accepted media)
ability to upgrade to allow more formats
Accepted media:
CD
CD-R
CD+RW
CD-RW
DVD
DVD+RW
DVD-RW
DVD-RAM
Standard 5" and 'mini' (3"?) versions of above.
Manual region switch with ("Zone-switching",All,0,1,2,3,4,5,6,7,8)
Ability to disable 'forced' subtitles
No Macrovision
Permits skipping of 'forced' video (warnings, forced commercials, etc)
Plays NTSC and PAL discs, can output either as NTSC or PAL
VGA output
Other thiongs if I think of them.