Disabling my blue mouse button on my Dell Laptop

[nin137]

hi guys,
i have to do a lot of typing and almost ever other line i happen to inadvertently touch the blue knobbed button in the middle of my Dell Laptop's keyboard (situated between the G & H keys & above the B key). this is really annoying as it whisks the cursor into another part of my word document and inserts what i had been typing there. i looked in the control panel but couldn't find a way to disable this mouse option.
is there any place where i can disable it?

[glc]

Look in the bios.

[nin137]

thanks i will give that a try, this thing is absolutely driving me nuts!