Dell Dimension 3000 Locked up

My daughter has given me her Dell Dimension 3000 Desktop computer. She had removed all personal data so there was only software programs remaining. The computer was working fine when I received it. I deleted a Norton Security package that was out-of-date and loaded AVG's free Anti-virus package and Malwarebytes software to provide security for on-line use; the computer was still working fine. I then loaded Zone Alarm's free Firewall software. Since then, I have a problem every time I turn on the computer. It displays the Dell opening screen, then the Windows screen, then the "Welcome" page then I get the following screen (white letters on a blue background):-

A problem has been detected and windows has been shut down to prevent damage to your computer.
INVALID_KERNEL_HANDEL
If this is the first time you’ve seen this stop error screen, restart your computer. If this screen appears again, follow these steps:
Check to make sure any new hardware or software is properly installed. If this is a new installation, ask your hardware or software manufacturer for any windows updates you might need.
If problems continue, disable or remove any newly installed hardware or software. Disable BIOS memory options such as caching or shadowing.
If you need to use safe mode to remove or disable components, restart your computer, press F8 to select Advance Startup options, and then select safe mode.
Technical information:
*** STOP: 0x00000093 (0x000000A$, 0x00000000, 0x00000000, 0x00000000
Beginning dump of physical memory
Physical memory dump complete
Contact your system administrator or technical support group for further assistance

My daughter did not provide any documentation (either paper-based or on disc) with the computer and I do not know how to proceed. Can anyone, please, help me?

Best regards,

Bill N