We love board games - some of my newer favorites:
Settlers of Cataan - the premise sounds boring but it is far from it. It is somewhat like monopoly but is more random as the board is a puzzle of hexagons and each hexagon represents a commodity. Each settler is trying to build a settlement and the components of the settlements (houses, roads, settlements). If you decide on this, add the expansion pack so that more people can play.
Blokus and
Blokus Trigon are both favorites.
+1 for Apples to Apples - everyone in the family loves this game
A really old game that is difficult to find is called
Acquire - I played this game every night for years --- and it is a great combination of luck and skill so that everyone can play. I recommend looking for the old version with the raised board for setting the tiles in. We wore out 2 of these games and I have restocked them from ebay. This
Avalon Hill Game or this
MMM game are what you are looking for.
And
Taboo .
We like games that can transcend age groups. So that the adults and kids can play together.