Windows 7 is a good operating system. I can't fault you for sticking with it, it's what is on my new computer as well.
As for applying the cursor, try following these steps and it should work:
1) On your PC open your Control Panel.
2) Click "Devices and Sound."
3) Click "Mouse."
4) Select the "Pointers" tab.
5) Click on which cursor you want to change.
6) Click "Browse" and search your computer for your new pointer.
7) Open the desired pointer.
Repeat these steps until satisfied and then click "Apply."