Chamonix has it all, but don't be distracted: The mountains are really all you need
The idyllic town of Chamonix will demand your time and attention with its enticing cafes, bars, shops, and other distractions. But don't succumb to the enticement at the expense of nature. The fact is that the true beauty of Chamonix has been there for millennia and all you need to do is make sure you're wearing the right shoes and jacket and take a hike.
In a place like this, if you allow it to be about consumerism, you've really missed the beauty of it.
There are paths everywhere and the range of difficulty can be as simple as a flat, well-trodden path to a climb that requires ropes and carabiners and spikes on your shoes. I found paths to suit me perfectly: I was challenged, but I felt good at the end of the day. My muscles told me I'd had a workout, but nothing screamed at me accusingly.
So take the time to get a map with the trails clearly marked on it (there are plenty at the many tourism desks), and head on out. Save shopping for another day.