Cannot open Setup.exe for DSS driver

1. My techie level is FLINTSTONE. I reinstalled WINXPHome on a Dim4300 with Pentium 4, a CPU that hadn't funtioned up to snuff for several years. I followed the Dell instructions. The first time, I discovered I could not restart. So I reinstalled again. This time in addition I could not find the drivers to download and also found myself hounded by a pop up entitled "Status" that tells me it is an "Installation Package {*.msi}" located on a CD-
ROM that I don't have (I did find a file folder on the Reinstallation CD entitled "MSI" but it was "empty" insofar as "Installation Package" files are concerned). I read through as many forum pieces as I could referencing similar problems and was finally able to find and download the DSS file (and, I assume, using the same strategies, I'll be able to download the other drivers). But, as soon as the Install Shield hits the zip drive, boom...dead stop. I go back into the driver folder and click on the .exe icon and get "Setup cannot run on this machine."

Now what? I'm prepared to download the drivers one by one, but how do I run them after the download? What gremlin is keeping them from running?