Clutch fluid help?

I'm so sorry to be the one with 5000 questions lately. I got my TPS replaced, and it is starting like a champ now! Unfortunately, when I thought it would also take care of this shifting/clutch issue, it did not.

I have checked the fluid level and I plan to add some to it, but have one more simple question. The Haynes said the level should be to within 1/2 inch from the top. It is down about 1.5 inches. Would it being down that amount make it do this?

Again, the problem is:
intermittently, the clutch will get "floppy," and won't provide resistance until 2/3 through the stroke of the pedal. Then, once I've driven it for a few minutes, the problem completely disappears. Most days it doesn't even do this. But, when it does, it also resolves itself. When the clutch is acting this way, it also shifts rough.

Could this be the fluid still, with the seeminly small amount that it is low? AND, is it BRAKE FLUID that goes in this reservoir?

Thank you all, once again! You've saved me SOOO much money, and I've learned some awesome things! As my title states, I'm still a rookie!

Top up the fluid now!