Have you added any hardware that might conflict with the printer port? A sound card perhaps?
I would check the BIOS settings for the parallel port. Make sure it is enabled, and check the settings. You might try "EPP" setting, seems to be most reliable, or if that fails try "standard".
If BIOS is ok, then run a simple test of the parallel port. Boot with a DOS disk.
At A: prompt type
DIR >LPT1:
You should get a directory listing on printer.
This works best with a dot matrix printer. On a laser you may need to press a button on the printer to force the page to print.
If this works you are pretty confident the hardware is OK and you have a software issue.
If the DOS test fails, I would open the case and inspect the cable from the printer port to the mother board. Unplug and reseat it. Verify it is installed with proper orientation.
If the DOS test works, I would look at the LPT port in Device Manager for a clue.
You should see only 1 lpt port and it shouldn't be flagged as not working.
Either way, You can just delete the port and let PNP reinstall it. If you see any other devices flagged as not working or not found, these would be worthy further investigation.
Another thought. Have you installed any printers, FAX software, or scanners that might have installed software that "captures" the printer port?
If all fails you may really have a defective printer port. You never said how old the system is or if it ever worked.
BTW, reinstalling the OS sounds pretty lame for this kind of problem. I very seldom see parallel port problems. But it is a sure fire way to get rid of software conflicts!