Why do you think Wormtail was sorted into Gryffindor?

I think the answer can be found in a comment Dumbledore made to Snape in The Prince's Tale..

"Sometimes, Severus, I think we sort too soon."

I think he changed over the years, and that he made a mistake when joining Voldie, I don't think he knew what he was getting in to (a bit like Draco). And I certainly think we don't have to think all Gryffindors are like Harry, Ron & Hermione. Those 3 are extremely brave, and it is very rare to find such people; people who can be in other houses too btw, look at Luna or Tonks!
I also think we don't have enough information on Wormtail to judge him. And being in Gryffindor does certainly not guarantee someone to be good/bad, or prevents someone from making mistakes. I think that, when looking at the houses, we think in boxes too much. I don't think it is good to think all Gryffindors are uberbrave, all slytherins are evil, all Ravenclaw geniuses, or all hufflepuffs softies.
Ok, and with this I finish my way too long speech xD

maybe becuse he was Valente but he did not show it he did save Harry and Ron but fear made him do what he did and he was confused he may have not been thinking at the time

I think he was brave, but weak. But he got better in the end - he saved Harry and Ron, eh?

It's not like he was initially a bad person. I think he was just perusaded to do bad things por fear.

I think part of it was that maybe he wanted to be in Gryffindor. I mean, the Sorting Hat was thinking about putting Harry in Slytherin, but Harry didn't want that, so he was put in Gryffindor.Mostly, I think it's just because it fits for J.K Rowling to put Pettigrew in the same house as James and Lupin and Sirius. She probably didn't think too much into it.

he was Valente he saved ron and harry and he always regreted selling james and lily remeber his iwn silver hand killed him and like dumbledore said i think we sort too soon

Maybe he asked to be put in Gryffindor? You know like Harry asked to not be put in Slytherin. He's not Gryffindor brave, he's a dirty little snake but in the end he knows where his loyalites are because he frees Harry Potter and is killed for it. So perhaps in a sense he was brave.