If you haven't played these games there has never been a better time to experience them.
And boy, I'm glad I did. These games really do show what the Wii can do. Amazing artistic design has made these games practically ageless in terms of visuals. Metroid Prime 1 is 7 years old now and I got goosebumps when I saw the snowy landscape Phendrana Drifts for the first time. This is a testament to how amazing the guys at Retro really are.
Combined with the tight controls, the Prime games really are an immersive experience on Wii. Navigating the complex environments (which is what you'll spend most of your time doing, by the way) is really enjoyable. They are so cleverly designed that you have to watch out for little details. Cracks in the walls that you can't blow up yet, visible expansions that you can't quite reach.... Because you will have to come back and get them once you have found the right upgrades. The game deliberately teases you with just out-of-reach area's...and once you work out how to get to them the sense of reward is incredible.
Bottom line is if you like the legend of zelda and lateral thinking you will absolutely adore these games. I was a bit indifferent to the Metroid franchise before.. and now I've just come off a 6 hour marathon session and I've bought Metroid Fusion on the GBA. On top of that I'm finding out everything there is to know about the backstory of Samus and the history of the other games... and my obsession is all down to these three games. If you want something you can really lose yourself in, I can't recommend the Prime Trilogy enough.