Typically one wouldn't check out the branches folder... you'd check out one of the branches, if you needed a different branch you'd either do an svn switch in that working copy or check it out the second branch in it's own workspace.
Perhaps you could expound on what you're trying to do?
To answer your question it is possible to checkout just a directories immediate children with
svn co --depth immediates http://svn.company.com/repo/branches
But this would be a pretty non-standard thing... I'm not sure why one would do this, I'm curious.