Why does IE always open minimized windows when opening a new window?

I often have several minimized IE windows in the taskbar. When I click on some URL (e.g in an email) it opens a new IE window (which is what I want), but at the same time it also always opens at least one of the minimized windows and that I find most annoying (esp. if those contain some complicated page and the refresh takes 5-15 seconds during which time IE is unresponsive).

Why can't IE not open a new window without maximizing some other window at the same time? I then always first have to close that other window again.
Can one adjust or "tweak" that behavior somewhere?

Michael