Upgraded to Windows 10 Pro Anniversary (the last version that will work with this tablet.  They will support the same as Windows 8.1)
Did a "clean install" of Windows 10 Pro Anniversary to remove any "bloatware".
Downloaded and installed Network drivers from the Dell site.
Switched to Microsoft Edge from Firefox (much faster with the tablet)

The ST2 now works much faster with my email, browsing and Facebook.  I think the problem was with the original WiFi software before.

My only remaining problem is with the speaker volume.Both speakers are working. 

I've maxed every setting I can find, but it is still very low.  Is there a better driver or something else I can try?