As the detail oriented people at Cook's Illustrated are wont to do, they froze six different kinds of summer fruit, using several different techniques, to see which held up the best.
The overall verdict is that fruits must be frozen with some sugar (whether that's sugar syrup or plain sugar depends on the fruit). Fruits frozen with nothing added ended up with a mushy texture and off flavors when defrosted a few months later, according to the CI testers.
Peaches need some ascorbic acid to keep their color and texture, and cherries, unfortunately, didn't fare well in any circumstance. The recommendation? Can them instead.
• Read the article: How to Freeze Summer Fruit, from Cook's Illustrated