Windows 10: How do I change the profile or account of the default login

"when I went into it yesterday it was like none of my desktop shortcuts, themes, other stuff. Would those things be in David-Desktop? ... So copying the folders from David-Desktop (I haven't done this yet) to the new admin users folder would it set up the desktop how I had it before this all started? And if the new a/c works OK, then delete David-Desktop, sadly. "

Yes, you created a whole, new User with a default, empty profile when you made the new acct. To elaborate on Navy's advice- open C:\Users and you should see your new, working acct name and David-Desktop. Open each user in separate windows and just open each folder under David-Desktop with the info you want to keep (desktop, pics, music, etc) and drag over to the corresponding folder in the working User name.

To simplify things, if this is the only acct you want on the computer, delete all other users, like David-Desktop (double-check that you didn't miss moving any files to the working acct); go Control Panel (Search+type C or Action Center\All settings-type control panel in search box). Go to User Accounts>Manage Accounts and delete any extraneous users there. You will be prompted whether to keep the David-Desktop files in a new desktop folder (only if you think you may have missed something) or simply delete. Your new account, as an admin, should be the only one remaining. Run netplwiz again to verify and if you want to change the password req to log in, change it here. Good Luck, you're 90% there.

 

Thanks for your post mrgeek,
I have been trying to copy data across from the c:\users folder to the NewAcct and I've struck a lot of errors and other messages while trying. It's just getting messier and messier. I'm really grateful for the support I've received from this forum but I've made a decision to reinstall windows and make a clean start. I've learnt a lot from this post and will be able to manage my User account in the future. I'll leave it at that but thank you very much for your support Navy.