If you choose Arch you will learn VERY much, but it will take you some time and effort to get the system running as you like.
If you think that Arch might be a bit too difficult for you, then I recommend a distro that is based on the legendary Debian linux, and it is called CrunchBang.
I am currently using CrunchBang and even though it is a relatively easy distro to set up, it is more interesting and fast then say Ubuntu or Mint. CrunchBang is more elegant and less bulky. It also uses a very minimalistic window manager called OpenBox. It doesn't even have a full Desktop Environment like Ubuntu or Mint do.
You can check out
my desktop screenshoot to see how OpenBox looks. There are no icons on the desktop and you will learn to do everything using keyboard shortcuts. The file manager is also not necessary to use, as you can manipulate files very quickly and efficiently using the command line. Anyway, it is a fun distro. Give it a try and feel free to ask for any help or assistance if you ever get stuck.
Good luck mate, and always remember that the amount of knowledge and skills that you will learn and acquire is directly proportional to the effort you put into seeking those things.