is it possble to decompile UT GOTY\SYStem  *.dll files & have a look at the source codeS??

i have never tried to open a *.dll in my life and opening them in notepad just show  many strange characters... so there must be a way to decompile the file & so one can edit it or update it or what, =skip= ,

 please tell me how if you know / can anyone tell me what exactly these dll files do??

A .dll file is executable code. The files contain functions called by the game itself. Notepad won't show you much of anything useful.

It is possible to disassemble (decompile) these files to see their code in a low-level form (assembly language), but you will have a lot to learn.

You can use You are not allowed to view links.
Register or Login to disassemble Win32 .dll and .exe files. There are also freeware alternatives - just search for Disassembler in Google etc.

Modifying them is also possible using assembly language but it is a delicate process.

Impossible, the best you can do is generate a few headers out of it. If you are good with ASM you can read a bit of the code, but its hard.