4000+kbps is insane. Xvid is a much more optimized codec than mpeg2 and doesn't need this at all. Anything over about 2000 at that resolution is a complete waste. Heck the resolution is a overblown chewing up more bitrate than necessary too. You have to consider your source's resolution: you gain nothing adding lines that just aren't there. You could use 3/4 of the resolution without losing any original PAL lines and then set the bitrate to half and see no difference in quality with bitrate to spare.
My other concern is that the audio is a bit soft. Probably a result of the -32db normalization that is typically applied to ac3 audio for DVDs.
It's fine for standalone DVD players but too low for a PC. If you have the raw PCM audio and are sticking with 2 channels, the Xvid version would probably benefit from a good VBR mp3 encoding instead. Something like lame's --alt-preset insane. Ac3 is only useful on a PC for anything more than 2 channels.