Hello, there! NSMB, isn't absoulutly mind-blowinhg, nor does it match up to previous Mario side-scrollers, but it is awesome. It's a great addition to your DS collection and will supply oddles of fun for anyone. While it doesn't take long to get to Bowser (Using some shortcuts, aproximatly one hour), it'll take some time to to beat the game at 100%. I highly reccomend it.
I've never played SMRPG before, but judging by the ammount of praise surrounding it, the game is awesome. I think you should buy it and judge for yourself.
I don't know if we're allowed to talk about stuff relating to emulators, but I can tell you this; ROMs and emulators are highly illegal. Please don't download one, m'kay?