USB Keyboard not working after running Monolingual

Question

Okay, I'm not a Mac person and should have known that I was going to mess up my mother's iMac, but here it is -
In an attempt to improve the mac's performance I performed all of the actions described in the following article: 11 Ways to Optimize your Mac's Performance     ( http://lowendmac.com/eubanks/07/0312.html ). Basically, I cleaned up files and 'other' system preferences. Things seemed to be fine and the computer did run much better. However, after running Monolingual and deleting what I understood to be 'unnecessary' PowerPC files the standard USB keyboard is no longer working.
I've tried to search for various remedies, but have come to a dead end. So I'm left with reinstalling the Snow Leopard OS (I think it is 10.6.8?) BUT I can't because it is asking to input the account password (which I know) to make the change and I can't figure how to do that when the keyboard not working.
Any help would be great!
*feeling like a bone head*

Answer 1

How are you trying to reinstall Snow Leopard? If you're booting from the Snow Leopard or iMac Install DVD that came with the system then that should eliminate any of the issues you may or may not have caused when you deleted did the clean up work on your mom's system.
I suggest trying the following:
0) Verify that the caps lock key is off. It can make inputting passwords difficult if you don't realize it is ON.
1) Reset the PRAM by restarting the system then quickly press the command-option-P-R keys before the gray screen appears. Wait until you hear the computer restarts two times as indicated by the startup chime. For more info refer to http://support.apple.com/kb/ht1379.
2) If the issue persists after the PRAM reset then boot from the Snow Leopard or iMac Install DVD, whichever you have. Once you see the menu asking you to choose a language try using the arrow keys on the keyboard to move the language choice selection. If the arrow keys are working at this point it indicates your keyboard is at least partially functional. Go ahead and select the language then proceed to step 3.
3) Once the next screen appears move the cursor up to the menu bar area and pull down the Utilities menu. Select the 'Terminal' application. Once the Terminal application launches try typing the various keys on the keyboard and check to see if the correct characters are displayed. Please let us know if you detect any errors. If there are no errors then you should be able to quit the Terminal application and proceed with reintstalling the OS.