Risk is great....but it's nothing compared to my favorite war board games.....
*drumroll*
Axis & Allies and Fortress America.
Another great one is Supremacy - it's like a complicated risk with modern weapons - especially with the add-on packs
I also am a fan of the more classic games - Life, Scrabble, Monopoly, etc
Oh yeah, and, of course, chess. LOVE chess. Also cool is "3d chess" - not quite like the game they play in Star Trek but sort of. Basically it's 3 chessboards one on top of another. One person starts on one side on the top and the other person on the bottom on the other side. There are special spots for transferring between levels and there is a special spot for kings only to transfer as well.