Dell makes it annoyingly hard to reset BIOS passwords. Their official FAQ on the matter states that you have to call them and verify ownership, and then they will be able to help you in some way.
From what I've found, there's no button or jumper to clear the CMOS, but you can always try removing all power sources (AC, battery) from the laptop and then removing the coin cell battery. After a few minutes any residual charge should theoretically drain, resetting the BIOS and removing the password. After a few minutes you can try plugging the laptop in (but don't put the coin cell back in yet) and boot. Once you've verified that the password is indeed gone, power off the laptop, put the coin cell back in, and reassemble the laptop.
The Dell 700m service manual is located here if you want to look into this option. It would mean partially disassembling the machines, but I don't know how many other options you have here.
http://support.dell.com/support/edocs/systems/ins700m/EN/SM/index.htm