Do you have a spare HDD to test with. I have seen HDD's that are on their way out cause Page Errors and cause programs to take forever to load etc. If you have a spare HDD available large enough to install the OS and game, try that and see what happens.
Otherwise if you dont have a spare HDD available, locate the make/model of the HDD and download and burn to disc or bootable thumb drive the HDD Diagnostic for this drive or use a tool like Crystal Disk Info to see if the drive reports any issues.
http://crystalmark.info/software/CrystalDiskInfo/index-e.html