Here is the scenario ... I am also using tortoise SVN ...
I can create a new folder and do a checkout with the "only this item" option ... this will checkout just the top level folder, I can then go into the repo browser and select any subfolder i want to "update to revision" (in the repo browser right click, select update to revision) ... this will bring down only that subfolder ...
Is there a way to remove the folder without removing it from the repository?
If not, my other option is to simply checkout the subprojects individually (this might be the best solution), lets see if anyone has an answer to the above.
I'm a bit late to the game but I've just had the same question and not found a satisfactory answer.
The answer I came up with was to do a full checkout then
ticking make depth sticky then retains this depth over future updates.