cant install notebook system software

I have an inspiron 1501 running windows xp sp2. I just reinstalled windows now im trying to install the drivers and utilities. I found the info page on the order to install them, the first step is to install the nss. when I attempt it tells me that it cant be installed. Is there a way to see if this has already been installed. If not how do I get in to install. while following the instructions of the order of installation, I notice that there are either multiple and/or different versions of things. should I install All of these or just the latest version. any other helpful advice is greatly appreciated. thanks Felicia

Thank you! It's long time, Is there an rignt answer for the problem? I've been concerned about the issue, Would you pls post it here?