Yep, that's it! ^_^ Though you remember more of it than I do. XD I remembered that the innermost circle was a frozen lake that Satan was half-submerged in, and that the sinners frozen underneath were condemned to suffer eternal pain as they cried and the pressure from their tears built up around their eyes, with nowhere to escape to.

Also, if I remember correctly, Dante was able to ascend to Purgatory by climbing over Satan.