There's usually a keyboard shortcut to disable the trackpad. On my laptop, it's Fn+F6, but it's probably different on yours.
I would think restarting the computer would reenable it, so i doubt it's the problem, but you never know.
Failing that, do you have a USB mouse you can try?
It could be that the track pad has simply failed like explained above, or what happens a lot is there can be a button used to turn it off, literally. I am not sure if this is on Compaq also, but on HP Laptops, in the upper left of the track pad there is a little curved indent, and if you double tap it with your finger the track pad is disabled but you can still use any USB attached device. Note that when this happens there is usually a little orange or red light that turns on near it. Also, your driver could have crashed or have been disabled. Look up how to reset device drivers and follow the instructions. Hope this helps, have a wonderful rest of your week!