500 Error after changing permalinks and site URL info

I noticed that the home page for our site (atlantayogaconference.org) was not going to the Home page I created (atlantayogaconference.org/home/), so I changed the permalink settings to %postname% and site URL to atlantayogaconference.org/home/, but that didn’t help and now I can’t get to the site at all, including wp-admin.

I went to the GoDaddy server and copied over a vanilla wp .htaccess file, but that hasn’t made any difference. I also edited the wp-config and functions.php files in the Themes directory according to the instructions here, one after the other then tested, and neither worked.

I have Weaver II installed, but don’t think that has anything to do with it. Everything was working fine until I started playing around with the permalinks and site and home URLs.

Any ideas of what to investigate? I’m not a professional web dev, so layman’s language would be much appreciated.

Thx.