when i try to do anything inside of the sitemap page, it crashes and sends me back to the admin homepage.

if i try to change the pagination from all to 20, it will crash.
i check the index boxes for the url's and press save and it will crash.

i do not know what i am doing wrong?

Hi,
You shouldn't be displaying all your URLs on the Sitemap page, as it usually causes server's limit on number of submitted variables to be exceeded.
If you can't even change the number of displayed URLs, try closing your web browser and opening it again - it should reset number of URLs displayed to your default setting from Joomla's Global Configuration (the Default List Limit option).