You are a math major, at least IT will be helpful to transfer to IT.

I am a software developer. I want to learn VB and DELPHI as soon as possible, which is relatively simple and easy to get started, but there are not many companies using it now.

Now it is basically. NET and JAVA C++, and that needs professional training to get on the job.

If you want to do research for a long time, I suggest you start with strata's machine linguistics, such as assembly language, which is relatively low-level, and then learn C language and take your time.