Hello Russ and welcome to Seven Forums.
It's possible that by manually deleting files from Windows 7 some system files may have become damaged or corrupt and are now preventing the installation of IE9. Try running a system file checker scan from an elevated command prompt (option two.) If problems are found, run the scan 3 times and reboot the computer after each scan.
SFC /SCANNOW Command - System File Checker
If there are no integrity violations you should be able to proceed with the IE9 installation. The suggested install method (including prerequisites) is outlined here:
How do I install or uninstall Internet Explorer 9?
If IE9 still won't install you may want to review these troubleshooting steps:
Troubleshoot problems when you cannot install Internet Explorer 9