I like the Big Mac. They're doing that 2 for $5 deal right now - fuck the fries and coke, I'm getting two Big Macs!
Honestly not that big of a fan of McD - don't like most of the menu. Actually not a fan of most fast food. 98% of my fast food purchases have been the Baconator combo from Wendy's. Fucking love that bacon'n'cheese, and nothing else compares IMO.