I'm sorry if I'm coming off as harsh or mean, I'm just trying to explain that what you think is coding, actually has nothing to do with coding.
The .INI files you're referring to, are plaintext files that contain data we can modify. It doesn't perform any logic like a program, it's just data to be used for a program.
A .DLL file is a 'Dynamically Linked Library', and contains machine code like an .EXE (Executable). The human-readable part you see at the end of the files are called 'Strings'. These are sequences of bytes that represent words used in the program.
Unfortunately, you can't open/modify either a .DLL or .EXE in human-readable form. (Technically you can 'disassemble' it and read the translation of the machine code, but that's not easy at all)
Basically, you'd have to make your own mod from scratch if you want to do anything.