Thanks everyone!
I'll check out the Famicom Contras as soon as I get a Famicom. Due to money troubles tho that might not be any time soon. In the meantime, the Contra game I'm playing the most is Operation C due to it being on a portable system (thus I can play it while away from home or while my DVD Recorder is busy with something else).
I've also been checking out a few Contra clones, namely Irem's Gunforce series which I own thanks to DotEmu's Irem collection. For some reason, everyone regards the first one as a terrible game, but I don't see much wrong with it except that the controls are a little weird (you know how in Contra you just point in a direction and they're just magically pointing there? The Gunforce dudes need to swing their arms into that position, which means you can fire in an arc but also means you're a little slower than you would actually like to be in this kind of game). IMO, these games are also hurt by their almost total lack of any sort of plot or premise--particularly the second game (called Geostorm in Japan), where I'd really like to know what's going on.
The Gunforce team apparently went on to found the company that made the Metal Slug games, of which I've played the first one. I do have one criticism--only being able to shoot in the cardinal directions. Its like the AVGN said: "it seems like only Contra got it right."