1.) Windows is not Linux and vice versa
2.) There is no such thing as a software manager in windows such as there is in Linux Ubuntu.
You install software from the downloaded file (installer). You uninstall it from the uninstaller file (located under Start Orb / All Prgrams / The app folder there) or from the Programs and Features icon in Control Panel
3.) Rhythmbox does not seem to be a Windows compatible software (Linux Only)
4.) Compiz to the best of my knowledge is Linux Only. If someone can make it work on Windows, would be HUGE.
5.) Linux Programs are not compatible to Windows unless someone makes a windows version.
6.) Practically every game on the planet is Windows compatible, it just depends on if it was developed for Windows 7. Not all older games will work in 7, and my guess is those games just are not compatible. There is no Wine equivalent for Windows.
You will need to find the Windows version of those software, or find an alternative.