Somehow, i've "expanded" all my tracks vertically, even unused ones..is there any way to "collapse all" to get them back to their "original" vertical sizing?

I don't understand how you could do that .. or I don't understand the question
Can you post a Pic?

Edit*
I simply held the CTRL button down and gave the 'scroll wheel' on the mouse a spin.
This was while the mouse was hovered over the tracks view. The CTRL key caused the tracks to expand vertically.
Spinning the mouse the other way made them all adjust back.

I guess the expected behavior is;
If you use scroll wheel on your mouse while hovered over track window, it expands horizontally

If you hold CTRL down while making the same maneuver it expands vertically.

Rharv - holding Shift expands things left to right. Holding Ctrl and scrolling expands up and down.

Thanks...I'll let my cat know so that next time she will be able to correct it!

Good tip Simon. Thanks for posting!

Jeff

If you are in the Tracks view, and the mouse is over the data area, the scroll wheel causes horizontal expansion (in my experience)
No need for shift key, but it is a good tip to know about.

If the cursor is over the track Name area then the scroll wheel scrolls up/down through the tracks instead.
This is one of the behavior aspects of RB that has taken me a while to get used to.

The 'Shift' trick is new to me, so thanks.

Sorry guys, I was wrong about the Shift thing - I think that was leftover information in my head from another DAW.

As before - scrolling in the data area expands horizontally. Holding Ctrl expands vertically.