For a triangle side solving program I wish to have the top part of the screen a graph with a triangle and letters to correspond with different parts of a triangle. Then below I want to have an area where the user imputs numbers for all known sides. My problem is that when I put my calc in horizontal mode I cannot seem to get the fullscreen command command to work. It even stay in horizontal mode in other programs until I reset my ram. Anyone have an idea what to do to fix this?

You mean the Full command? If you're using TI-BASIC, that's all you need in order to switch from G-T mode or Horiz mode back to fullscreen mode. Are you sure that you're running the command? Did you try running Full on the homescreen, or even just going to the [MODE] menu and setting it manually?