Well, it's a magazine about Game Boys, isn't it, so you've got to have a Mario game in here somewhere and Super Mario Land 2: Six Golden Coins is a perfect example of how to do a platorm game right.
The Mario games became instant successes because of the immediately accessibility of the gameplay. You literally pick up and play - no previous skills required. You control the titular hero in his quest to find six coins which fit in the final castle and allow you to save Princess Daisy from Wario. As with all Mario games, you spend all your time running very fast and jumping gaps whilst trying to land on moving platforms instead of rows of spikes.
Power-ups can be collected; the first of which increases Mario's size and gives you a period of invincibility if hit. Other 'costumes' include Fire Mario (can shoot fireballs) and Carrot Mario (allows you to fly), and each of these allows you to access secret areas of the many sideways scrolling levels.
Super Mario Land 2 is a real Game Boy classic. The addictive action is always on tap, the levels are varied and test all comers, and Mario's vast repertoire of moves means you're always in control. If you want just one platorm game in your collection, make it this one.