I added a skin to my site settings page and not the home page i was going to try it out on now I can't access any of the admin settings to go back and change the skin to default. I am getting a server error code 500. Any tricks to fix this without access to the host/admin menu items?

If you can browse to /admin/pages, you can highlight the page(s) in question and change the skin applied to them.

If not, and if you can get to the file directory then rename the folder that holds that particular skin file. Then it can't be applied.

If neither of those work, I have some other, more dangerous, approaches.

But, before doing anything please make a complete site backup.

In the future, consider making full site backups before making changes like adding modules or skins. Or, do that first on a copy of your site.