In contrast, the CGI portions look really-really bad(this includes any live action with CGI effects). This is a shame because the CGI looked sooo good when the series was aired. They took the 4:3 video source, cropped the top/bottom and then scaled the image to eliminate the black bars.
On 4:3 the CGI is still letterboxed, but sharp. It's got the usual artifacts from being too sharp, sometimes :) Are you really running at 720p vertical or 480?