You talk about Taskbar window size, then modding the appearance of files in your system files, so I'm a little confused what you want.
That Taskbar looks fine to me.
How did you mod the system?
So I modded my appearance files in my system files(?) a very long time ago, and now I'm sick of looking at my fake Windows 7 appearance. Does anybody know how I can go about and fix this? Here's a picture to show what I'm talking about: