Sounds nice. First, here is the site on which you can track the leaf color progress, keep it and refer to it as your trip gets closer. It is not active yet, but will be.
Where to go? Depends what you want to do. Lake Placid is beautiful and interesting, as is the entire area around there. Great hiking, camping, and hotels in the adirondacks. Want to have a bit more luxury? Stay at the Sagamore.
Here is a Lake Placid guide that talks about fall colors, as well as activities, lodging, etc.
Thank you rjr0810 and Rhapsodyinblue for your reply. both are very helpful!