I took a good look at BASIC and GW-BASIC for DOS.
But I prefer a language, where you can compile the source with a runtime-engine of some kind, to create a self-executing file - to protect your source code. BASIC and GW-BASIC are(generally speaking) open-source programmers - at least the BASIC/GW-BASIC programs I have seen can all easily be loaded and the code tinkered with.
Euphoria seems very good - about half way through the huge manual!!!
"An expert is someone who will tell you why you can't do something." - Alec Issigonis (designer of the Mini)