Most soundtracks are opportunistic messes; Mystery Men is first-class opportunism and hits all the bases well. You’ve got your unavoidable radio hits (Smash Mouth, Freak Power — a.k.a. Fatboy Slim). You’ve got your ironic covers (Violent Femmes torpedoing the Stranglers’ ”No More Heroes”). You’ve got your blindingly obvious clas-sics (”Disco Inferno”). No trailblazing originality here, but no duds either.