We provide a concise approach to generalized dilaton theories with and
without torsion and coupling to Yang-Mills fields. Transformations on the space
of fields are used to trivialize the field equations locally. In this way their
solution becomes accessible within a few lines of calculation only. In this
first of a series of papers we set the stage for a thorough global
investigation of classical and quantum aspects of more or less all available 2D
gravity-Yang-Mills models.Comment: 24 pages, no figures, some sign errors in Eqs. 52--59 have been
corrected (according to the Erratum