Wend your way up into the Jura for the best view in Vaud
Especially if you are travelling with children, but with or without kids, if you are heading from Geneva to Lausanne on the A-1 (the only fast road in that region), consider taking a few hours to head up into the Jura Mountains to stretch your legs a bit.
At the Signal de Bougy, which you will reach by wending your way east then west then east again (and again and again and again!) through the vineyards that cling to the foothills, there are farm animals for the children to enjoy (I believe they can even pet a few), an extensive playground that is appropriate for all ages of kids, and a simple but very pleasant restaurant with indoor and outdoor seating. If you are traveling without kids, you can take in some spectacular golf with a view unlike any other in the region. It's pricey, but it's worth it if you can do it. And if you aren't a golfer or don't have that much time on your hands, just enjoy the walk and the view -- Lac Leman lays before you with the Alps rising behind. On a clear day, you can see Mont Blanc. Stunning. Just stunning.