I needed to do some screen captures and recordings of SSMS and realized this is a common problem that many of you could use some help with. There is a freeware tool called Sizer (thanks to Paul Nielsen for telling me about it) that lets you chose your window size. I downloaded the zip file instead of the msi because I didn’t want to install anything. The extracted executable works perfectly as a portable application. After double-clicking the Sizer executable, an icon resembling a plus sign appears in the system tray.

Figure 1. Sizer running in the system tray.
When Sizer is running, it adds a window size menu to all of your windows. To access this menu, you must place the cursor over the edge of a window as if you were going to grab the edge and resize the window.

Figure 2. Notice the resizing handle (white vertical double arrow) along the right upper boundary of the window. When you see this, right-click to bring up the Sizer menu.
Once the menu of standard screen sizes appears, pick the size you want and your window will automatically resize itself.

Figure 3. Sizer menu of standard screen sizes.
You can go to the system tray and right-click on the Sizer icon to configure it. You can add your own custom window sizes as I did.

Figure 4. Sizer with 1280x800 added.