Configurable via GUI applet. Compiled into kernel with most distributions. Configurable via text files. Yes, from lowest level to highest. In some areas.
All applications scriptable with any scripting language.
Scripting support must be specifically coded into place, and even then limited to that particular application and scripting language. Pervasive multithreading Yes. Maximum efficiency via very fine task granularity. Yes, but less efficient, much more coarse. Threads are known as processes.