My advice would be to stick to something as close as possible. You have a N900 or a N9? Great. There are plenty of cool things you could do with that.

You could simply start scripting on the terminal, Python is great, but I guess developing for those devices certainly calls for C++ in combination with Qt, or leave the Qt out of the equation and simply start with C++ on the command line.

Forget about Assembly, for now. It is lovely, it is beautiful but it is not true that that would be "a simple best start" to learn programming. It's not. Actually, the real best start would be a piece of paper, a pencil, a brain and some mighty interesting ideas.

http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html

http://www.cplusplus.com/doc/tutorial/

http://awelonblue.wordpress.com/2012...pen-and-paper/