Opening Preferences Crashes CC 9.1

You've tried pretty much everything, I think. I suggest you post a bug report in the official Adobe feedback forum, where Adobe wants all product feedback:

https://feedback.photoshop.com/photoshop_family/categories/photoshop_family_photoshop_lightroom

Adobe often engages meaningfully with such bug reports.  Include the summary of everything you've tried, rather than linking here (Adobe tends not to follow links). Also copy the first ten lines from Help > System Info.

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"(b) opened and Store Presets in this Catelog is checked (other changes on other tabs are accepted).  (b) is the more common behavior."

Try making a new catalog and see if the issue happens with it (perhaps the problem is specific to the current catalog).

Try changing the Windows number format:

https://helpx.adobe.com/lightroom-classic/kb/lightroom-crashes-opening-preferences-win.html

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How do I look at my original post and the replies in the Lightroom Forum? There is no apparent link from my account and when I search by my user name or "Preferences" my post does not show up.

Click the bell icon (top right on the web page) to see notifications, there will be a link to this thread.

First of all – did you update the graphics driver?

Second – try running LR as administrator. Right click the LR shortcut and choose Run as administrator.

Third – make sure that you have READ and WRITE permissions on the Preferences folder under your user name.

Fourth – if nothing of the above works, uninstall Lightroom, then run the CC Cleaner Tool followed by a reinstall.

Crashing when trying to open preferences is usually caused by the GPU.

And disabling the GPU is done in the preferences.

So as David suggested, try updating the graphics driver.

If that doesn't help, you have to edit the preferences file to disable the GPU.

With Lightroom closed, use the File explorer and go to
C:\Your user name\Home\AppData\Roaming\Adobe\Lightroom\Preferences

Open the file Lightroom Classic CC 7 Preferences.agprefs in a plain text editor like Notepad.

Close to the end of the file, there are two lines that read

useAutoBahn = true,
useGPUCompute = true,

First, set useGPUCompute to false, save and close the file, then try to launch Lightroom.

If it still crashes when trying to access preferences, try setting useAutoBahn to false as well (Lightroom must be closed).

Save and close the file, and try again.

Only thing that pops  out in your sys info is the GPU driver has an update 

25.20.15002.58

1/10/2019

sounds like contact Adobe

2. Please post your System Information as Lightroom Classic reports it. Standard request for diagnostics. In Lightroom click on Help, then System Info, then Cooy. Paste into a reply. Info from first line down to just past plug-in info.

1. Too contact Adobe, in any Adobe web page, and in any Adobe program, typically in Help, contact Adobe, this will launch a Chat. Describe problem, begin the Chat, and request contact.