I had a look around the game files for you, this may or may not work. I haven't tested it.
In the Dead Rising folder, browse to data\controls. In there you'll find 3 text files keymap, mousemap, padmap. You can edit any one of these and remap the controls to what you like.
For example: Changing W to arrow key up - Open keymap.txt Go to: COMMAND_KBOARD_EMULATE_LTHUMB_UP( KEY_W, HELD, ....) and change KEY_W to KEY_UP you can adapt this for any other mappings you want to change.
Keep in mind that there are other actions assigned to W, such as COMMAND_AI_VEHICLE_ACCELERATE. To avoid editing them manually, you could use the Replace (CTRL+H) function in Notepad to speed up the process. Remember, always make a backup.
Supposed fix for the 360 wireless controller not working on the PC version. I haven't tried it myself though.
Copy to your DR2 game folder. Run it. Load the 360 wireless controller default Controller 1: Force feedback tab - turn force feed back off Advanced tab - turn native mode off Options tab: Change Fake API from normal to compatibility