Typically, you don't need to enter the BIOS in order to use an external monitor. It is a matter of pressing the function key for your system to toggle between the display options (LCD only, external display only, or both LCD/external).
If the links and suggestions privided by April_12 don't help, you will need to contact Acer directly for help. Be prepared to provide proof of ownership of the system in question.
On these forum's it is not permitted to provide advice on how to break/crack passwords.
Solved both problems. Reset the pass word by pulling the battery on the motherboard and reinstalling it. That did not solve the external monitor problem but did give me access to the bios. I then downloaded the vga drivers from Acer and loaded them into the laptop. That solved the monitor problem and allowed me to toggle to one or the other or both monitors.
Thanks for the info anyway.