If you can get the sourcecode for a game or program does that mean that you can pretty much put it onto the gp2x??

Sometimes. Some programs are too demanding (e.g. it might be completely ridiculous like Quake 3 or an N64 emulator, be too reliant on floating point code, etc.), or have requirements for things that aren't present on the '2x like the X Windowing System, or controls that won't be very compatible. The things that port most cleanly are SDL applications.

Don't put a million question marks in your title, be more descriptive. It's exceedingly annoying to see threads with names like this.

ok sorry. i will and thank you that answered my general question. i wasnt trying to get very in depth there i was just trying to get the basic idea since i dont understand much about coding.