I'll start by first talking about WinXP.
In WinXP, you could configure the taskbar by first right-clicking on it and then clicking on the "lock taskbar" item (which had a checkmark to indicate it was locked). This would unlock the taskbar, and you could move it, resize it, reorganize it, etc.
Now the standard WinXP taskbar was what I call "1 unit in height", and everything was on just one row. That meant the Quicklaunch area, as well as the active task rectangles... all in one row.
But with the taskbar unlocked you could alter that appearance and behavior. You could for example "pull" the upper-edge of the taskbar up, until the taskbar was now "2 units in height". This now allowed for TWO rows of items, arranged in either of two formats: (1) all Quicklaunch icons on the top row, and all active task rectangles on the bottom row, or (2) all Quicklaunch icons in a 2-row collection on the left side of the double-high taskbar, and all active rectangles in a 2-row collection on the right side of the double-high taskbar.
If you used the (2) arrangement above, and you had your taskbar "unlocked", you'd see a vertical dotted line separating that left section (for the Quicklaunch items) and the right section (for the active task rectangles).
If you wanted to alter your taskbar presentation in this double-high format, you would first unlock the taskbar, and then drag that dotted-line separator either left or right or up or down (it never was really clear to me what I was doing, so I would just fool around until I got it the way I really wanted it).
When that dotted line turned into a "separated dotted line, with a short dotted line on top and then a small space and that a second short dotted line underneath) you had accomplished the 2-row presentation with Quicklaunch icons on the top row and active task rectangles on the bottom row.
With the dotted line "solid vertical", as one dotted line, you had accomplished the left/right presentation.
Then, you'd again right-click on the taskbar, and click on the "lock taskbar", and the dotted lines would disappear and your designated presentation would now become permanent.
Ok... back to Win7 and your issue.
I never knew you could even do what you've done, which appears to resemble the "left/right" presentation of a double-high taskbar in WinXP. All of what appear to be like a Quicklaunch icon area in WinXP is on the left of your Win7 taskbar, with the active rectangles appearing on the right.
I didn't know this could even be done. It certainly is not what the normal Win7 double-high taskbar presentation looks like when assorted program items are "pinned to taskbar".
In normal double-high taskbar format, it's simply a continuous set of icons and rectangles occupying the two rows as needed. There is no collection of icons on the left (in 2 rows, as yours shows) and then "active" rectangles on the right (which in your case has oddly filled the entire top row).
Do you have any modifications to the taskbar? Are you running some 3rd-party modification? Any customization from some "how to" tutorial, as to how to get what looks like the old WinXP Quicklaunch bar into Win7?
I run my own taskbar also as double-high, as you do. But I do not have any Quicklaunch-like WinXP-like customization. It's standard Win7 format, just unlocked and dragged to double-height and then locked.
It looks as follows:
