what do the codes 161, 163, 301, and 173 mean?

That is a memory count, followed by various BIOS setup errors and (301) a keyboard error. That answer assumes that your laptop conforms to the IBM BIOS Standard.

i would be inclined to change the BIOs backup battery for the BIOS errors and push each key up and own a few times for the keyboard problem.

You don't say what the laptop is an so it is difficult to help further.

T
February 2009