After you manually removed the program files, did you run a good registry cleaner? If not, try the following:
1) Manually delete all VMWare program files and directories. You might even want to find the directories under the 'Users' directory and delete those too.
2) Run a good registry cleaner. I also use Win 7 (x64) and I have found RegCleanPro by SysTweak to work very well.
3) Open Control Panel-Programs-Uninstall a program - just to verify that the registry cleaner removed the old uninstall entries.
4) With VMWare completely removed from your system, try a fresh install of VMWare version 5.
5) If that works, try starting your version 4 VM. Make sure to get the VM to update the VMWare tools.
I used VMWare Workstation version 8 (Player version 4) for a couple of years and upgraded to version 9 (Player version 5) with no issues. One thing I did notice is that I like creating my VMs with Workstation rather than Player. The Player creation process never seemed to work all that well.