My girlfriend and I play a lot of board games etc, there are some great ones. And if you ever go to boot fairs you can pick up some really cheap.
Some of my favourites:
Boggle:
A game with a set of dice with letters on, you shake them up in the container (which makes a wonderful noise) then you have a timer and you have to make as many words as you can from adjoiningg letters.
Scattergories:
One multisided die with most of the aphabet on. each player has an answer sheet and pen and a catergory card. Each player uses the same category card. The timer is set, the dice rolled and you have to find an item for each heading on the catergory card beginning with that letter. for example car parts, cities that kind of thing.
Trivial Pursuit:
Everyone knows this.
Monopoly:
Again, everyone knows this. However it can also be adapted into a drinking game. We did this at uni, every time you passed go a shot of whatever was to hand was added to a pint glass. If you got sent to prison, you had to down the lot. Also you had to have a couple of fingers of beer everytime you had to pay a fine etc. Started slowly but once all the properties etc were purchased, it got very messy very quickly!!
Valve