Yeah, I figured, since it was just an SNES rom, and it wasn't really a test, I played it after NSMB because I wanted a mario adventure fix, I didn't try anything else because I was tired of messing with NSMB Wii so much.
Today I got to try more games, and play Kirby's Return to Dreamland, and that worked in any level I went to (I went to several worlds, and no disc errors). Also, I cleaned the Laser (I think), with my Wii Lens Cleaner (The odd disc shaped cleaner that was free at sometime when some users were having trouble with Smash bros back in 2008). I tried NSMB Wii even after cleaning, and I got the same disc errors, 3-1 wont let me play it anymore (My favorite level too, because of the penguin suit.)
I have come to the conclusion, my Wii is fine, along with the Disc drive/laser, its just my NSMB Wii disc has gone bad it seems. This kind of thing happened with my Mario Kart Wii Disc, the intro would freeze with disc read errors. I took it to my rental store that has a really nice CD buffer that deals with scratches. That was the WORST thing I did. When I got home after buffing it, the Disc read errors were UP the skyscaper...I couldn't even get past the main menu screen lol.
This is the 2nd time I have had to get a replacement disc...it bites.
Anyway, thank you guys for helping me, I appreciate you helping a newbie on the forum, lol.