Lived in Evanston for 10 years so feel somewhat qualified to comment. Downtown Evanston (just two stops off the purple line before the stadium at Central) has some amazing places to eat and bar hop.
If you're with family, I highly recommend stopping at the Lucky Platter on Main Street which has fantastic comfort food. The sweet potato fries are ridiculous. Just around the corner from Lucky Platter on Dempster is Cross Rhodes (Greek) which has killer gyros and other home-made Greek cuisine. Try the lemon fries (again with the fries!!??). Yeah, they are something special. If you're looking to get hammered in the downtown area, there's no better spot than Keg of Evanston on Grove St. I cannot tell you how many nights (and some days) had me stumbling out of there not entirely sure what had just happened. And lastly, Tommy Nevins Pub. Classic Irish restaurant/bar with live music and that laid back atmosphere you might be looking for before getting ugly at the stadium. Last time I was there, Bono was just leaving. Seriously.
The great thing about Evanston (and Chicago in general) is that you can get hammered pretty much anywhere, and have no need for a car at the end. The purple/red lines should be able to get you safely to most places you'll need while visiting. Just don't go too far south on the red line after hours or it can get dicey :-)