Nobody?? :?

Greetings - Newbie, be kind. I recently switched from Windows 7 to Windows 10. Try as I might, I could not get by 1998 CD or the smaller version of the 1998 CD download to work. I almost gave up. I did chuck the CD, which I now greatly regret, but life goes on. I tried again today to get back and I downloaded the full version of the 1998 CD for those dummies (me) who do not now have the CD and the associated patch. It works! My issue, perhaps a small one, is that I can’t seem to find a way to enlarge the game screen. In my Windows 7 version, it filled my screen, in the new Windows 10 screen it does not. It’s more a square in the middle of my monitor. When I try the Alt/Enter/Enter shortcut, it toggles between a tiny screen and the square one.

Any thoughts on how to get the full screen which fills my monitor again? Thanks in advance.