What the other guys said... just go play the Trilogy now that you've got it, the games are absolutely marvelous. The 2D games are practically standalone games, they are pefectly playably and make 100% sense if you haven't played any other Metroids before, so you don't need to play any of 'em for chronology purposes or anything.
Even the Primes can be played very well as standalone games, as the story isn't that relevant to them, in the sense that it's not like you wouldn't understand what's going on if you didn't play one. Just play and have fun! 
*Edit: as for the sensor bar I'd go for the official one. Usually better quality and saves you batteries. 
Plus the wire is very thin, really, so what discomfort could it realistically cause? Unless you have some huge big-ass setup and need to have your sensor bar away from your TV...
Nintendo Network ID: Cheebee 3DS Code: 2320 - 6113 - 9046
