DELL Vostro 1500 ethernet controller download???

appears to be this one as it is the only one listed

Since you reloaded XP you may not have reloaded your drivers in the correct order you can find that order listed HERE.

Not doing this can result in drivers not being recognized and installed properly

ok... so i have the disk that has the drivers, but it wont let me reinstall it or even delete the old one

try booting into safemode. Press the F8 key at the Dell splash screen. once in Safemode try installing/reinstalling the driver.

There is the possibility that you may have to reinstall windows all over again.

When you are in normal windows open device manager and note any devices that have a ! or X next to them

i have already tried that and windows wont let me install or uninstall anything when in safe mode

What do you have listed under network adapters in Device Manager and are there any devices with ! or X next to them

ok... so i have the disk that has the drivers, but it wont let me reinstall it or even delete the old one

You can't uninstall the old drivers, or install the new ones you mean?  What happens when you try to install/update the drivers?

Have you tried the drivers off the Dell website - as opposed to the ones on the CD - which are undoubtedly older?