This thread is not bad, but no one really delved into Va-Hi, Decatur, Brookhaven, Vinings, about 90% of Buckhead and Midtown, all of West Midtown, and a number of suburbs, some of which have some pretty cool spots.
Rule from a longtime Atlantan - don't stay downtown and if you do, don't go anywhere there except one of the stadiums, the Aquariums/museums or the CNN Center. Go North or East, young man.
Brewhouse is one of the best soccer bars in the US. It's in Little 5. You'll be shunned if you don't know your shit though. You are also in the minority if you're American, regardless of who is playing. However the English and Irish speak pretty good English, so allow them to be your guides.
Check out Stone Mountain as well. The carving is obviously controversial, but it is one of the largest rocks in the country (really, it's a huge rock without many trees on it) and you can climb it fairly easily without any gear except some decent athletic shoes with tread.
Swallow in the Hollow is also solid for BBQ. This is not Texas, so you may want to try to pork here (either ribs or chopped).
Just speaking solely of ITP, you can be in a million different worlds in one day. It's a very low-key diverse city. Buford Hwy, for example, has cuisine from dozens of countries on just a mile or two stretch. Decatur will have you thinking you're in the Bay Area or Greenwich Village, but parts of Buckhead will have you thinking you're in Miami or Southhampton. I now people from each area that has no idea how to get to the other or why they'd go. It's pretty funny, actually.
Enjoy. This is a truly underrated city.