You must unlearn what you have learned. Yoda - The Empire Strikes back
Having worked with Windows 7 for a few weeks now, when working with the taskbar, hover don't click. What I mean by this is with XP, taskbar interactions require a lot of clicks. If you want to minimize an application, click its name on the task bar. If you want to give the application the focus you click it.
Well doing that in Windows 7, always seems to result in two clicks. One to select the application you want, and once to select the Window. But this is not what you want to do. Instead, try hovering over an application on the task bar. The open windows for that application will automatically pop up. If you hover over once of the mini preview windows as shown above, then Windows 7 hides the other open windows and highlights the window being hovered over. Once you know which window you want, then you click it.
Its a completely different mindset, but once you get used to it, hovering will become your friend.