Metroid was the very first game I ever played (excluding arcades). I got it on my B'day with the NES and SMB. Some of my cousins and friends crashed my place, we decided to play Metroid first (since no one had played it yet). From the moment the game loaded, we were glued to the screen... we didn't stop playing till we realised the sun was up - and when you're that young an all-nighter was a big deal!
The game, the atmosphere, and having my closest buddies around made it a night I will never forget. Till this day, Metroid has a special place in my heart (along with back to the future ). It remains my favorite game ever. I'm yet to play any of the Prime series, and hope I can get my hands on them before corruption.