Is Microsoft Visual C++ 2012 also okay and can it run on windows 7? Will it works the samen as 2008/2010?
VS 2012 has added some new restrictions that breaks the build. You have to delete some lines, as shown in the attachment of http://bugs.openttd.org/task/5375#comment12071
What is the link to the source, at the wiki is a dead link.
What link are you talking about? Please be more precise in your statements. "link does not work" is difficult to decode when there are several links at many wiki pages, and where some of those links are not supposed to be viewed with a browser.
For now, I assume you mean "svn://svn.openttd.org/trunk". That link is not dead, you need subversion (svn == subversion) to access it, your browser does not speak "svn:". When you click at the link it is telling you that.
And have I download the openttd-usefil.zip and the source, or only opentt-usefull.zip?
The source is useful if you want to build the libraries from source code. If you don't want to do that, use the zip with the pre-build libraries (at least I hope that's it, I never looked in the file).
Where can I found Subversion command line version, since the link is broken.
You know of this thing called Internet right?
It has very nice services to find sites, if you don't mind telling commercial companies what you kind of commercials you want to view.
Anyway, if you had used such a service, you could have found the new home of the subversion project, namely http://subversion.apache.org/
Good luck with continuing your adventure.
It may be useful to join the #openttd irc channel for help, there are several people there that know about windows and compiling OpenTTD. It's often easier to interactively talk someone through the process.