Setting the game resolution smaller than your screen size is an easy way to handle the problem; of course, you do lose some screen 'real estate' doing so. It may not be a big issue if you're using a higher resolution - say a 4k monitor and running the game in 1920x1080. In that situation you could fit a good sized game screen as well as Tracker, Combat Reporter, and maybe a few other things on a single screen. Even if you don't have a huge monitor, you may decide losing a bit of space is preferable to spending the extra effort to get it working in "Fullscreen Windowed" mode (see below) just right.
If you do want to use all of a single monitor for the game, using windowed mode has more to do with how the game renders windowed vs. fullscreen mode. The game tends to handle windowed mode better both in terms of performance and in the ease of accessing other applications, but doing so introduces the application title bar at the top and window frame around the sides. I've tried tricks in Windows to remove these, but the game does not respond well to it. If I had succeeded doing that, it would have been equivalent to the "Borderless Windowed" mode you see in a lot of games today. Instead, I settled on hiding the title bar and frame offscreen, which I describe how to do in the "Fullscreen Windowed" Guide referenced above. It is the way to get "the best of both worlds" - the game running in windowed mode while enjoying a fullscreen experience.
If all this "fullscreen" vs. "windowed" stuff is confusing, think of fullscreen mode as an automatic transmission in a car. The game is figuring out how to "shift" the game window to use the whole screen for you. Windowed mode would then be a manual transmission - it has the same number of gears as the auto (i.e. a windowed application can still fill the entire screen), but now you're responsible for "shifting" the game to where you want it to be.