Questions about wp_loginout

I’m using wp_loginout for the first time for a client and I had some questions on how to make it work properly for my client’s site.

For starters, I notice the text for the link is ‘Log In’ and ‘Log Out’ and she wants it to read ‘SIGN IN’ and ‘SIGN OUT’ instead. How can we do that? What file would I need to tweak?

Also, I notice when I click on the link I’m taken to the wp-login page for what essentially is the CMS. I don’t want people to see that. Is there a way to create a page template that also has the login form but they see it as a part of my clients’ site?

Sorry for the NooB questions, but I haven’t dealt with this before.