One of the Xbox's greatest features of allowing players to view the games in ether high-def or standard-def seems to have been forgot by Capcom in Dead Rising. Internet forums are flaming away on how the in-game's text are un-readable on normal SDTVs and users are claiming that the game must have been test only on high-def sets. This 'bug' effects nearly every portion of the game as the player cannot read anything in any conversation or receive the games instructions when viewed on a normal TV. So far there hasn't been any fix released, but Capcom is aware of the issue. We are sorry that we don't have a fix for you but just a warning to the owners of standard-def sets, don't buy this game - yet.
NOTE: We could not find any screenshots of the issue indicated above so if any of you are experiencing the same issue, feel free to send over a pic of it and we would gladly post it. Thanks
Read: Capcom forum post
Read: Xbox.com forum post