I appreciate your comments. I'm aware that I could use Xampp and the php version that is currently delivered with it should be fine. Do you know if I can install PHP ONLY, i.e., not install mysql or apache? perl would be ok since I use it only once in a while. I would be willing to do that...
My concern with doing it the way you suggest is that when I've tried to do something like this in the past a new install breaks what's already configured and working. config. files are overwritten, libraries are in different places, and other dependencies seem to crop, etc. I tend to choose the default installations for most things. It's a habit developed over the past 35 years of installing this stuff. If you try to get cute or attempt to outthink these installs - you pay a price. So, while I can appreciate that the developers and implimenters of these things do the best they can to package this stuff so it's as flexible as possible, it's been my personal experience that it can takes hours and hours to figure out where everything is - update configuration files and get things working again. I just don't have the patence to experiment with it at this point which is why I'm asking for help BEFORE I try it. I'm looking to solve a problem - not create a bigger one.
It seems the one application that I want to upgrade requires at least php version 5.1.x ... so at a minimum I need to get to that installed. Still that will require a fresh install and given what I've got, I just need the proper configuration options and it (crossed fingers) should work. I may just have to take a chance and give it a whirl using the defaults.
thanks for your advice.