If you use the 'Prnt Scrn' button, chances are the screenshot you've taken that is either stored in memory or written by the game will be as detailed as you see on the screen. In order to preserve as much of this detail as possible, you will need to either keep the file prepared by the game, or save the screenshot as a BMP file (Open Microsoft Paint, and paste the image stored in memory). BMP files, however, are typically very big.
If you save it as a JPEG, you will have considerable space savings, but quality will be reduced (although sometimes imperceptibly) compared to the original, even if you set conversion settings to '100% quality'.
Some software will allow you to choose 'Optimal Huffman' encoding when converting to a JPEG. This results in bigger JPEG files (but still smaller than BMP files), but at 100% quality, the picture will look just like the original.
The excellent FREE image software, FastStone Image Viewer, offers this option -- and we've used it ever since we discovered it.
Force Better Quality
If you are playing an older game, you may occasionally be able to force superior graphics quality from the game, above and beyond what the game designers intended. Typically, you would do this through your video card software, selectively turning off options that say 'Application Controlled' and selecting your own.
You can, for example, do this for Dungeon Siege II and receive slightly better quality through superior anti-aliasing, but at a substantial performance cost. You can see the case study here.
What To Do If Your Computer is Slow...
If you haven't updated your computer in a couple of years, you may actually still be okay taking screenshots from the games we profile. This site is not about advertising the latest games with the latest eye candy: It's more about what you might have overlooked in software you already have as an art resource. So, chances are, the games here will run comfortably on your computer.
That said, once you turn on all the graphics bells and whistles, you may find that your computer is sluggish and may show 'lag' or 'stuttering' in certain areas of the game. If you want to preserve as much quality as possible, and maintain the best and highest graphics settings allowable, there are a few things you can do:
Turn off music and sound effects. Don't just turn down the volume -- turn it off entirely (although most of the time, turning down the volume using the game menu will have the same effect). And turn it off in the game. It's not the same if you turn down your speakers to zero because the game doesn't know that and is still using computing power to play sound and music. Music, in particular, can really drain resources as the game not only tries to keep it playing in real time, but may be switching to different tracks based on different events in the game.
Run in Full Screen mode. In Full Screen mode, the computer doesn't have to keep track of as much since you've dedicated it to running the game. If the game doesn't automatically save screenshots in a directory for you, you'll have to swtich out back to your desktop to save a screenshot (using, say, Microsoft Paint).
Unload background applications. If you're running things in the background, wait for them to finish first, then unload anything unnecessary. If you want to unload your virus scanner or stop real-time scanning, disconnect from the internet first!
Buy a better video card. If you absolutely don't want to buy a newer computer, you might consider upgrading to a better video card if you have a desktop. Laptops may occasionally be upgraded, but it's a bit trickier and you should consult the manufacturer first.
Reduce Shadow Detail. If you can stomach the sacrifice, reduce shadow detail a bit. Some games have a very high setting that calculates shadows to an unrealistic sharpness that you might not like anyway.
Reduce Reflection Detail. You can also reduce reflections. Some games have high settings that may result in unreasonably clear water with mirror-like clarity, which may or may not be important to the shots you wish to take.
If you are utterly desperate to take a screenshot or run a particular game, even at the cost of inferior graphics quality, you can try to force lower quality through settings on your video card, and selectively turning off options that say 'Application Controlled'. Read the options carefully to see what would be lost. This would be the reverse of forcing better image quality, discussed above.
If nothing works... If none of these work for you and your computer is still slow (or if it hangs!), then look at how old the game is. If it has been three years or more since it was released, for goodness sakes, do yourself a favour and get yourself a newer computer! Just a decent contemporary one with a reasonable graphics card should be more than enough to run even new releases fairly smoothly. It's best if you also had a larger (17"+) widescreen monitor to go with it, to reduce squinting.
If you like to let your mouse do the shopping or like researching many options online, try Amazon.com for new, discounted, or used computers. Amazon also frequently has customer comments about merchandise, so you can get word-of-mouth information before making a final decision.
Desktops are cheaper and can be upgraded, repaired, and customized more easily. But if you're not a techie and aren't going to tinker with your computer anyway, notebooks can be nearly as powerful, and convenient because they are portable and have less cords to worry about.