Microsoft did NOT delete the game from Windows 7. I did a default install and it's on my system. For some reason the feature must have been removed from your system.
You should be able to turn it back on again following the instructions below, which depend on "Control Panel" being configured as a sub-menu of the "Start" menu:
Start -> Control Panel -> Programs and Features
Click the "Turn Windows features on or off" link in the left pane
Find the "Games" feature and click it so that it's checkmarked, then click "OK".
If "Control Panel" is NOT a submenu of the start menu, then you can set it that way by doing this:
Right-click "Start", select "Properties"
Click the "Start Menu" tab
Click the "Customize..." button
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