How can I reset the BIOS password for a laptop ?

If you open up a laptop (usually through 30 or so screws on the bottom) you will find a normal cmos battery affixed somewhere.  Simply unplug the batter, wait for about 5 minutes, and plug it back in.  This will reset the password as well as all bios settings.

This apply for Desktops not for Laptops as almost all of the newer laptops store their BIOS passwords in a manner which does not require continuous power, so removing the CMOS battery may not work at all.
My laptop does not seem to have a battery or is either burned on the motherboard or is well hidden.

You are right removing the cmos battery will not reset a bios password, this will work on some older laptops but nay built in the last 3-4 years will have a security chip that stores the password. From the sounds of it you probably have a bad motherboard. If the laptop is still under warranty i would contact acer. Most laptop manufactures require you to ship the system to a repair facility to reset password. The only one i know of that doesn't is Dell they can generate a master password based on Svc tag and other information, but you are unable to even type anything in so if acer does something similar it still wouldn't work. There are ways i have heard of, shorting out the security chip but it can also brick the system. I would definetly contact Acer.

Actually, this method has worked on new Dell XPS laptops among others.

http://www.tech-faq.com/acer-bios-password.shtml

Quick break down. To change the bios password you will have to send it in and pay 100 dollars, it is not covered in a warranty and they don't save their passwords to the BIOS/CMOS, but in an EEPROM.

My guess and your best bet is get it serviced for being broken and hope that is covered in the warranty if it still exists.

"Resetting an Acer BIOS Password Using Hardware
If you cannot boot the Acer and don't want to send your computer back to Acer for an unknown amount of time, you can try to reset the BIOS password via hardware.

Tech FAQ Forum members have reported that they were able to remove their Acer BIOS passwords by simply opening their notebooks and removing the CMOS batteries for 30 minutes.

Once your BIOS password is removed, you will need to press the <F2> key during POST (Power On Self Test) to enter the Acer BIOS setup."

This is a snippet from the above mentioned web page.  However, if your keyboard is non-responsive, I would consider getting the notebook repaired anyway.  If you have the hardware, back up all data before sending the notebook in or taking it to a repair facility.  More than likely, they will wipe the data.

My laptop is no longer under warranty and I would rather buy a new one then have it fix by Acer which would charge me a lot for that.
I can not see any battery on the motherboard to remove it. Where can that be?

From what I have read about your specific laptop is that the battery is soldered to your motherboard. I am unsure if you can remove it. I also don't think your bios is causing the doom to your keyboard. Have you tried plugging in an extra  keyboard through a USB jack to type with and see if that works?

I have tried plugging in an extra keyboard through a USB but it did not work.

PS/2 also? My USB keyboard won't work without it actually being in windows, might be the case why yours isn't either.

What do you mean by PS/2?

http://en.wikipedia.org/wiki/PS/2_connector

Is there anyway to reset that password?
What else should I check apart from what was specified above?

If you had another manufacturer, it would be rather simple, Acer stores it too differently for most normal procedures or workarounds to fix. You may have to get a new laptop.

So....shall I understand that there is no way to reset an Acer laptop password?

Of your specific model short of bringing it or sending it to a acer certified tech, then the answer is no. The bios is held in the EEPROM which is a flash ram and isn't affected by the removing of a CMOS battery or the jumper switching to default.

I did read that you may be able to unlock your keyboard with FN + F7 or
Hard power-off (hold the power button until the laptop turns off)
Unplug the AC adaptor
Remove the battery
Plug in the AC adaptor
Hold ctrl and turn the power on. You should arrive at a black screen.
Hard power-off again, then turn the power on.

If these above tricks work to free up your keyboard then great, still no answer on the bios though.
From everything I have read this is "normal" and has been happening a lot since october 2007 on the models that came out around the same time.

In all truthfulness, get a new laptop that isn't an acer and hook up the acer to it, transfer whatever you want to keep and get rid of the old one.