Best way to "un-version control" a file?

I'm a new SVN user. I just checked in a small project to a
repository. All the functions I tried work s not real problems

But, I did not think until now that I should have excluded files such
as core files and logs and autoconf's cache from version controls. I
now know how to a global ignore and a ignore foe one directory but how
to remove these files from version control once they are already
there. Is "svn rm" the best why? But that will remove them from
the working directory too. I don't want that.

Next is these a way to make the ignore property for a directory apply
to all sub dirs recursively. The next project I want to move to svn
is much larger and has many nested directories

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Chris Albertson
Redondo Beach, California