Quick side note on the topic. The answer to your question is it depends on distance. Out to 75 yards I'd go with the 12 ga. Beyond that I'd go for the ML or 30-06. If you simply must have one now and you're going strictly for deer and possibly moose type game at short distances then I would look at a NEF Sluggers. Great guns at good price. Thinkin about buyin one myself. Here's the link
http://www.hr1871.com/Firearms/Shotguns/ultraSlug.asp