After upgrading to Windows 10 I have experienced no technical issues with most of the Ys games (Oath in Felghana, Ark of Napishtim, and Ys Chronicles) however for some reason, the game seems to not want to stretch to wide screen even with the "Stretch Widescreen" option ticked in the configuration file. The Screen Resolution is set at 1024 x 786 and can go higher if necessary.

Also when seeing the FPS in Felghana and Napishtim, it appears to go way into the 1000-6000 FPS range which is well beyond the recommended 60 FPS as I understand it. Not sure if this means the game is running much faster compared to when I ran it on Windows 7 previously or if its using more resources than necessary. I'm mainly curious about why it is has so many more frames now.

Am I missing something? Of course the game won't be widescreen at 1024x768, it's a 4:3 resolution. You say the resolution can be set higher, so pick a widescreen one and see if that makes a difference. What's the native resolution of your screen?