Did you do this below?
This is called the BSOD (blue screen of Death) this usually occurs if you have recently installed either a new piece of hardware with a driver that has conflicted with Windows.
1. Unplug all you USB peripherals while the PC is shutdown
2. Press F8 while the PC is booting up its difficult to know when to do it so I usually press it twice with 5 seconds between presses.
3. Select last known good configuration and see if your PC will start this might be all that it needs.
If this fails unless you have a boot CD that allows you to recover the DOS or on some laptops like Evesham they have PC angel installed I am not sure if the Compaq Presario has this but you can use
Hirens Boot CD or some other to try and restore the files,
I am sure that the CAB files that are required will still be on the laptop unless someone has removed then to save space.you may have to take it back to factory defaults, you will loose all installs and documents though its a bit drastic but it should get you back up and running.
Hope this helps please rate my post if it helps you.