Yes , I can help you.
Can you give me your system information by filling this form:
Video Card : If you don't know it go to run , dxdiag and you will see it there.
Ram Cards : Go to Control Panel , System
Processor : See above
If you don't have a good computer the Windows 7 can make you some problems.
It can't run properly cuz the computer is requested.
Try to reinstall Windows XP and sure it will work properly.
Don't forget to say thanx xD.