Oh yeah, Giverny is a good option...not too far and very picturesque, like Monet's art. Bruges is also quite beautiful, especially the market square, medieval architecture and all the canals. And if anyone in the group is a Tintin fan, there's a shop not far from the plaza where you could easily blow all your vacation money on memorabilia! :)
One thing I will "caution" though about Bruges is that it doesn't have a nightlife, so by 6-7 pm, the streets empty out, stores close, and it becomes more quiet and "residential" with people coming home from work. So, if your group was planning to have dinner there, there's not a lot of options, except maybe around the market square, although I did finally find a superette near my hotel after getting hopeless lost for a couple of hours (labyrinthine streets, no signage, no street lights).