Simple question about Categories

[ramm4]

Hello,
I must be missing something. I have a lot of sub-forums (see screenshot 1). I like the way this is organized.

If the user clicks "Albums", however, I do *not* want them to be able to post in just the "Albums" category (see screenshot 2, where I circled).

I know that I can simply fix this by making the forum "act as category", but the problem with this is, it is it no longer organized nicely on the main page (screenshot 3).

So, how can I simply disable their ability to post in "Albums", but keeping the nice organization like in screenshot 1 on the main page? I will have 21 sub forums and I can't have that long of a list on the main page.

Many thanks