@phillylive when you say "crashing," you mean it kicks you back to the command-prompt? And it sounds like you already have a keyboard connected, so you should be able to correct it this way. Type exactly:
nano ~/.emulationstation/es_settings.cfg
(Make sure it's all lowercase like this, and that squiggly dash is a "tilde," not a regular dash. Single space after nano, no other spaces.)
Scroll down to the string section (past all the bool and int values) until you find the line that says:
<string name="ThemeSet" value="your_problem_theme" />
Change the value to "carbon" (the default theme), then press Ctrl-S, Ctrl-X to save and exit (if you make a mistake, you can exit without saving by just using Ctrl-X; tell it "No" when it asks if you want to save anyway.)
Then you can type emulationstation to restart ES, or you can reboot.