It sounds like you're actually looking for a "sparse checkout" containing only items of interest to you: http://svnbook.red-bean.com/en/1.7/svn.advanced.sparsedirs.html
That chapter of the SVN book gives far more detail than I can cover here, but the quick-and-dirty is (for the command line) that you can use svn checkout --depth ...
followed by svn update --set-depth ...
commands to build a working copy including only the directories and files of interest to you, that will remain in that state even through update and other operations.
You mentioned TortoiseSVN, as well. You can do the exact same thing in TortoiseSVN using the "Update to Revision" context-menu item on each file or folder in your checkout, but a much easier way is in the "Update to Revision..." dialog for the entire working copy, or the "Checkout" dialog. These dialogs have a "Choose Items..." button. Clicking that button will present a directory tree where you check or uncheck items to include in you working copy all in one operation when you complete the update or checkout.