constantly crashing

No matter what your operating system may be, when it gives you illegal operation errors in abundance, it is time to format the hard drive and reinstall the OS. If you have a second drive or partition, or even a zip disk or cd burner, you should do abackup of anything you want to keep (my documents, favorites, etc...). Bear in mind, you will have to reinstall all of the applications (MS Office, etc...) after a fresh copy of the operating system is installed. If you're not familiar with this, orare not comfortable doing it on your own, seek a professional in your area to help or do it for you. Best of luck.

I agree with papajohn.

I would however, check the hard drive, cpu and memory for problems first.

Run a thourough scandisk on the drive.
Make sure that the fan and heatsink for the cpu are not encrusted in dust.
Remove and re-seat the memory.

Short of re-installing the OS, you can get some improvement by using a good registry cleaner.
Such as Norton WinDoctor or OnTrack Fix-It.
Both do a good job of cleaning the junk out of the registry.

If you haven't done so, make sure to install updated Windows components. This can make a difference too.

When you clean off the drive, make sure to do a full hardware inventory first, and download all the latest drivers for your hardware and OS.

Install the motherboard drivers before installing individual device drivers.

This would be a good time to consider an OS upgrade to.

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