my computer’os is fedora 4,w.m. is KDE
I want to install fvwm,I’m a beginner .
Welcome to the forums, ycyahcn! 8)
Not sure if you are asking a question, or making a statement, but if you need more info on Fvwm have you looked at the Official Home Page, yet?
Let us know if you have any questions… 
Thank you at first.In my college computer’OS is Windows.I think Windows like a blackbox,although it open a part of resource code.I want to learn Linux,C,JAVA.I want to know which distribution is suitable for me,however such as KDE,GNOME is too big and that take much system resources,so my computer is to slow,a friend told me FVWM take a little.
thank you ,could you give me some suggestions? 
This has nothing to do with FVWM. Any distribution will do. Some will
suggest Gentoo, others Debian, Fedora, etc. For the record, I use Debian.
– Thomas Adam
Yes, Fvwm can take a while to setup if you write your own configuration. You could use a ready-to-go config written by someone else and be up and running in a few minutes. Whether you write them or you use someone else’s, that’s just up to you.
Look here for some ready-to-use config files: viewforum.php?f=39
One of the other WMs you mentioned might also work for your needs. You’ll need to try several of them to have a good understanding of what you want and need, and how they compare. Nobody here can determine that for you.
Good luck with it, whichever route you take. 
thx!