You're using 2.4.2.

None of your links are working, in fact, except the login screen.

However, I think the problem lies somewhere in your URL setup. The blog is using this URL:
http://www.guidedsolutions.net/index.php/blogs/?disp=catdir
which goes to a 404

However, it should be using this one:
http://www.guidedsolutions.net/index.php/?disp=catdir
which works.

The other broken pages are the same. Have you done anything to your blog settings which might have changed the URLs? If so, undo it!

Where in the Admin area should I be looking to fix this? As far as I can tell there are two tabs where it asks to specify a URL, but I don't know what to put in those areas and cannot find any documentation that explains in detail how to set this up so it works. Thanks.

If you have not fiddled with these settings already then leave them alone: the defaults should work. Have you made any changes to these settings, or are they still set to the default values?

I'm pretty sure the defaults are the problem in this case because (I'm pretty sure) the defaults select the "pretty URLs". Which I think is the problem.

On the Blog settings -> URLs subtab, select the option for each section that looks like parameters instead of folders, meaning ?foo=bar&this=that instead of /bar/that/

If it works it is because your server doesn't support "clean" URLs, but I always forget what it takes to make your server handle that stuff.

Thanks, EdB ! The parameter idea worked !