Liam Neeson, Ewan McGregor, Watto, some of John Williams's scores, TPM duel was pretty good, some elements of the Jedi and their routines, Christopher Lee, Yoda on crack in Episode I, Samuel L. Jackson being pissed at other Jedi as Mace, and TPM's Dolby EX soundmix.
TPM is the best prequel. The others are only bad 1080p videos.
No one really got to act in these films, save for Neeson in some scenes of TPM.