I have to admit, I was going to give you no stars because it just doesn't seem worthy of a star to me. This will explain my thinking:
Concept:
--I HATE trailers. The very fact that this is a trailer makes me hate it, but I gave it a fair shot, just by watching it.
--Secondly I'm tired of Super Mario Brothers, they aren't that great, NG grossly overrates them, and they're old. Seriously guys how many more parodies of these guys can you make? They're plumbers!
Audio:
--It distracted me badly.
--It didn't match what I was seeing and only added an unorganized randomness that I didn't enjoy seeing.
--If anything the choice of putting it into your flash was one of the worst decisions you made.
Graphics:
--Here is where I am most lenient, I know drawing and animating is hard, at least for me, but some things just need addressed, like your backgrounds. I know you think they're humorous but they too just confuse me or anger me. They're either a bunch of random colors put together or far too plain.
--The characters were probably your best feature in the whole flash. They still need work, but keep trying and you might have something.
--When Mario blasted the goombas, (or shroom people whatever) it was both cliché AND unrealistic, as well as poorly animated. I'm sorry but it's the truth.
--When you add words to the actions, it distracts me and reminds me of the worst batman movie ever made, which in turn angers me more as it was an extremely sad portrayal of batman.
Other:
--There is no replay button.
--There is no scene select.
--There is no mute.
That's all I feel I need to say, I'm sorry if I offended you, this is made to help you, not crush your hopes and dreams. Keep practicing.