I have selected ten trees that will do you proud in a small yard. These trees have been recommended by urban foresters representing several urban forestry associations. These trees are small (most less than 30 feet tall) and have showy flowers or fall leaves. Every tree can be planted in many North American tree zones, is compatible with most utilities and structures and can be found at online and local nurseries.
Each tree is linked to a great resource called a Fact Sheet developed by The United States Forest Service and the Association of State Foresters. I use their information in the introduction of each tree.
Here are the trees you need to consider when you have plenty of room:
Domestic Flowering Dogwood - Photo by Steve Nix, Licensed to About.com