Photoshop :: Can't Fresh Install From CS2 - CDs App Install Option Is (Grayed Out)?

I  have CS2 Premium which I'm running on an older PowerPC Mac (G5  -  Dual 2.3 GHz ) running OS 10.4.11. I've had this setup for many many years (registered/activated with Adobe) but suddenly one day I could no longer launch my Photoshop app: when I clicked on the Pshop icon it would start the launch (open) procedure ...  and then almost instantly it would quit (in just a few seconds ... before the application even got to the 'title/credit' screen).
 
I've recently tried uninstalling CS2 (everything except Acrobat) and I ended up doing a manual uninstall of Version Cue. I've been on Macs for 20+ years so figured this would be a pretty straightforward procedure - uninstall -> reinstall and then back to work.  Nope.
 
I'm attempting a fresh installation direct from the original CS2 CDs. In any event, when I try to (re)install CS2 - and after going through the standard screens with Adobe's usage terms agreement and installation hard disk selection -  I arrive at the screen where one selects which application(s) to install by checking the various boxes (or alternately, to install the entire suite) but the 'Adobe Photoshop CS2/Adobe ImageReady CS2' line and checkbox are grayed out, so it will not allow me to check them and continue with the Photoshop installation process.