You might want to try and isolate the issue. It would suck to send your Wii off to repairs and later learn that you had a bad cable/display/game disc. Have you seen these bad pixels in any other game?
"The worst part about these reviews is they are [subjective]--and their scores often depend on how drunk you got the media at a Street Fighter event." — Mona Hamilton, Capcom Senior VP of Marketing
*Image indefinitely borrowed from BrainBoxLtd without his consent.