I asked the same thing here: http://miui-dev.com/forums/showthread.php?254-Is-there-a-way-to-turn-off-the-unread-messages-counter-in-the-stock-messaging-app
There isn't a way to do it with out editing the system files or something.
Can somebody that talks to them ask if they can put in a setting to turn off the stock SMS counter?
Sent from my ADR6300 using the miui-dev.com Forums App
Also, this app. has a bunch of android themed wallpapers.
http://www.appbrain.com/app/android-fun-wallpapers/com.sancron.wallpaper.androidlogo
Also, if you look under "more apps" they have quite a few other apps for wallpapers.