Yes, there are many Firefly props and sets that could be taken directly from a Western. They even added Western-style slang into the dialogue.
I like how Captain Reynolds was kind of a bastard (albeit moral) in the first episode or two. In have the DVD set. In the commentary, it's revealed that the network forced them to soften up Captain Reynolds to make him more likable.
Bill Shatner and DeForrest Kelley actually starred in a lot of Westerns before Star Trek.