I'd listen to the first album, followed by the Self-Titled and lastly Champion, which is their second. Champion was good but my least favorite album of theirs.
start w their first cd, then go in order, cause honestly its a progression. and every cd is amazing in its own way. they truely are on of the greatest underrated pop punk bands out there. hopefully this will get them them credit they deserve. i doubt it though....thanks victory.