Peter Pettigrew - Timothy Spall
Peter Pettigrew is the human reincarnation of Ron Weasley's pet rat. He's one of the earliest villains in the Harry Potter franchise. Spall's costume was a combination of special FX and makeup, minus his transformation scene. That was all CGI.
The Lizard - Rhys Ifans
The Lizard in Spider-Man is obviously a huge CGI feat. Creating something that looks this good and supernatural in real life would be difficult. The incredible post-production work combined with Rhys Ifans' portrayal of the horrifying lizard man was a huge hit with the fans.