We will describe certain moduli spaces for monodromy-Stokes data for linear connections on vector bundles of rank 2 over P^1 with regular or irregular singularities associated to 8 types of Painleve equations. There are 10 types of such moduli spaces corresponding to the types of singularities of connections. Each moduli space becomes a family of affine cubic surfaces, whose equations can be explicitly given. We may also discuss the moduli space of parabolic connections with prescribed regular or irregular singularities over a curve and the Riemann-Hilbert correspondences relating connections to monodromy-Stokes data.