DOH! You're killing me. I really want to see these. I actually got a theme with red lines on the widgets and a droid bot on today's date on the calendar, but can't put up my shots until I get home. (I wonder if I can combine the new BGs with the red lines?!)
Anyway, you don't need to be rooted to do them (I'm not) and there is a thread here somewhere with instructions. Seems complicated, but once you do it, it's not that hard at all.
Edit: See
this thread for non-rooted screenshot instructions