Hi Myrna,
I hang around a lot, do a
lot of reading/learning and very little posting.
Hopefully the following information is correct and, if it isn't, someone will jump in and make it right.
First of all, I've followed your 'saga' from the beginning and give you a whole lot of credit for jumping into an 'unknown' and tackling a new format in the style you have when you're feeling so lousy. 'Congratulations' on your sticktoitiveness!!
I'm impressed!!!
Now for your 'clean install'... I believe you need to start up from the 8.5 install CD, as described above, go to the Utilities folder, as previously mentioned, and run Disk First Aid. If you've already done that, skip that step. Then, as others have mentioned, double click on the 'install' icon and when the 'Options' button shows up at the bottom of one of windows, click on that. If 'Update Driver' is selected, I'd deselect it because you're 'already there' but do click on the 'Clean Install' button.
Doing a clean install will put a new, pristine, blessed System Folder on your Hard drive. All the things you've mentioned above that you've added to your system will still be there lurking in the 'Previous System Folder' and elsewhere in folders on your HD.
When it's done, Restart from the Hard Disk, not the CD, and I'd rebuild the desktop at that point. Do another Restart just to make sure it's working OK and then restart again from the 8.6 CD and apply the upgrade.
If you have a way to download "Clean-Install Assistant", it's a wonderful way to add all the things back into your new System Folder from the Previous one. It's free to home users, was written by Marc Moini and works beautifully. The 'documentation' that's included with the program is very well written.
Hopefully this will all go well for you after your good night's sleep.
If you have any questions, please ask and I'm sure someone will come to your rescue.
Good Luck and I'll keep my fingers crossed that this all goes like clockwork!
Laurel