Help mirroring image on hdtv

My computer monitor is hooked up to my computer via dvi and my hdtv via hdmi. I can easily extend the desktop to the tv, but when I tried mirroring the images, the aspect ratios were out of whack for both. Any help?

Thought my hdtv was 1080p, not 720p. Guess I can't mirror an image while keeping the native resolution of both.

Can I somehow play my games full screen on my tv using the extended desktop setting? Even though I'm sacrificing resolution, some games are nice to play on my bed with a controller. Netflix works fine like this.

Can I somehow play my games full screen on my tv using the extended desktop setting? Even though I'm sacrificing resolution, some games are nice to play on my bed with a controller. Netflix works fine like this.

Ross_the_Boss6