I would recommend:
- JCB Hall, 2008:
http://www.cdjapan.co.jp/detailview.html?KEY=AKB-D2015Great shuffles, good setlist and excellent camera work. However, it's quite old by now so you may want something more recent. This concert has been my favorite for a long time and imo it's one of the starting points of the rise of AKB48.
- Budokan, 2009:
http://www.cdjapan.co.jp/detailview.html?KEY=AKB-D2029It's Budokan! 104 girls, so you also get to see SKE48 and SDN48. Three concert days, including a shuffle concert. Day three includes the new Team announcement as well. Once again, quite old by now, but still one of my favorites.
- Yokohama Area, 2010:
http://www.cdjapan.co.jp/detailview.html?KEY=AKB-D2050This includes the first performances of the newly shuffled teams. It's probably the best 'recent' AKB48 concert. I dig the setlists for each concert, because they include both old and new songs. The picture and audio quality is really good. The best part is the montage. The camera actually stays on a girl for some seconds, rather than flashing between members every half a second. Great release for sure.