This mess started last week when my network card stopped working,I got a new card,but my pc would not install the drivers.when I swapped the new card for the old one,the pc would detect the new card,but as soon as I started loading the drivers I would get an error message saying problem installing this hardware.I
got a different card and the only way I could get it to work was formatting and reinstalling xp.
Now my video card is acting up(2 monitors blacking out and display problems).
I got a new video card and attempt to install it and have the same error message when loading the drivers.Iam really stumped on this one!!The pc will detect the new hardware,but will not let you install the drivers.

Let's see,

What brand and model are youre networkcard and vga card?

What drivers are you using?

And how are you trying to install them? It sounds like you are letting windows install the drivers for you.
The best thing you can do is to download the latest drivers and install them manually. (uninstall youre old vga drivers before installing new)
And if windows wants to install drivers after removing the old ones , just press cancel.

The network card is netgear and that is working fine.The new video card is nvidia.I was using the drivers supplied on the install discs.
The thing that I did not do was to uninstall the old drivers.What is the best way to do this??

Go to "add and remove programms" and find the driver(s) and un-install it.
Then re-boot youre machine and don't let windows install anything, just press cancel.

I don't know what drivers came on the cd but the ones from the Nvidia website are probebly newer:

http://www.nvidia.com/content/drivers/drivers.asp

I don't know youre O.S. so you have to select the proper ones youreself.

Download the drivers to desktop or where??

Doesn't really matter , youre desktop will do fine.

When youre ready with un-installing , just dubbelclick on the driver and follow the menu that comes up.

You can delete or move the downloaded driver when youre done.