Adjusting emulator settings
Next you need to run your (legally obtained) emulator on your PC, dig into the video settings, and find the full-screen resolution setting. Crank it up to match the maximum resolution of your HDTV. You might run into trouble with older emulators that offer only a list of fixed resolutions, as they may not go high enough to match your HDTV; if that's the case with your emulator, you’ll have to open the emulator’s configuration file and put your desired resolution settings in there manually.
Thankfully, this procedure is not as scary as it sounds. As an example, I configured the Neo-Geo emulation program WinKawaks to run at 1280 by 720 resolution by editing the WinKawaks.ini file (usually you can find a similar .ini file containing video settings in the folder that corresponds to your emulator).
Within the first 20 lines of the WinKawaks.ini, you’ll come across the following lines of text:
In those settings, simply change the 640 to 1280, and change the 480 to 720.
Save the file, and open the emulator -- and, whatever you do, don’t touch the resolution settings in the menu, or you'll overwrite the change you just made in the .ini file.
Now, if your PC desktop is showing up on your HDTV, you should be ready to rock. Of course, you have to tweak a few more video settings first if you want to get the best gaming results on your HDTV. Not all games or game emulators have these options; if you can make the following changes, however, you’ll obtain solid results.
Your first priority is to find and select the 'Maintain aspect ratio' setting. If you don’t, often you’ll end up with old games configured for a 4:3-aspect-ratio screen stretched out to match your widescreen resolution, and they’ll look terrible.
Next, you should enable the 'Stretch image' option if you can. I know I just said that stretching isn't advisable, but here's why you might want to do it anyway: Not all old consoles output a perfect 4:3 resolution. The NES, for example, had almost-square proportions, at 240 by 224. If you set up your emulator to maintain the original aspect ratio, stretching the image output on your HDTV just a bit gives you the best of both worlds and produces an image that's as close to that of the original game as possible. This setup is really appropriate for playing classic PC games in Windows 7, since it helps to ameliorate the issues with playing older PC games that use wonky resolutions.
Finally, determine whether your game of choice supports bilinear filtering. Turn it on in your older PC games, and they will look much better on your big screen. Your emulator may also support bilinear filtering, but be cautious: Image filtering is, to put it mildly, a contentious issue when it comes to emulator fidelity. Some emulators have a TV-mode function that you might want to try, but they are inconsistent and most of them don’t emulate the appearance of classic games very well; instead, enable bilinear filtering to slightly smooth the picture on your big screen without detracting too much from the overall classic-gaming experience.
At this point you should be all set to go. Start up a PC game, throw it into full-screen mode, and enjoy.
One final tip: Now that you’re up and running from the couch (presumably with a gamepad or two), you'll likely find it convenient to operate PC game menus without having to grab the mouse. You probably already know about the free PC-gaming application JoyToKey, which allows you to map PC keyboard keys to a button on your joystick or gamepad; what you may not know is that JoyToKey also lets you map mouse movement and mouse buttons to your gamepad's joysticks and face buttons, respectively. Give it a shot, and game on.