we ate at House of Blues a couple of weeks ago (8:00 PM dinner on a Saturday night) Food was good...what I'd call good bar food: burgers, ribs, etc. We enjoyed it. People have said it used to have a much bigger menu...we thought it was a pretty small menu (just 2 pages including everything)
The Drinks (adult beverages) were mixed strong. Service was fine. We were not on the dining plan for that meal, but we did use Tables in Wonderland card for the discount though. Waiter did mention that dining plan was acceptable if we had it. They do not allow dining plan for the Sunday Brunch: that was mentioned when I originally made our reservation.
Would recommend reservations, though...and when you get there, go inside to the inside check-in podium if you have reservations. There was a long, long, long line outside waiting to be seated--they were telling people at least 60 min wait unless they wanted to sit outside, and it was cold night so no one wanted to. But people with reservations went right in, checked in, and were seated within 10 minutes.