XBR Dosent Support Original Xbox Games?

[Starspin]

The Xbox Originals are in the same format as XBLA games. Is it possible to extract files from XBLA archives?

You can do it with a hex editor. The game data is stored in the Data files and starts at offset 0x00002000. In the Data000 file it should say something like "MICROSOFT*XBOX*MEDIA", which leads me to believe this is some kind of DVD image split into multiple files. Unfortunately if you try to edit the data files at all, the game will fail to load.