If you have time and want to discover the area, you can enjoy those 100km with scenic roads and it will take you 2h30 (if you do not stop which will be a shame). Leave Annecy, direction Veyrier du Lac, After a few turns stop quickly at the panoramic parking on your right, from there you have a lovely view on Château Menthon St Bernard.
Then drive past the Morette memorials (WW2) and reach Thônes the capital of Reblochon cheese.
Continue to La Clusaz, col des Aravis, la Giettaz, Megève and St Gervais. Stop whenever you wish to take a photo or enjoy a coffee.