Wirelessly posted
There at least used to be stock text-based themes. I don't know what is available nowadays. But that is what you are looking for. There is no way per se to turn off the icons. You are looking for a theme that meets your needs.
Checkout themes at
http://mobile.blackberry.com. Also do a search on blackberry themes for your model. Watch out though, as poorly designed themes can cause problems. Keep your device backed up if you begin experimenting with aftermarket themes.