As an experiment, I extracted the contents of NVE-188.8.131.52.exe and had a look at the directories contained within. Among others, there were dirs named Cover Designer, Nero Media Home, Nero PhotoSnap, Nero Recode and Nero Showtime. I deleted them and repacked into a self-extracting exec using Best compression algorythm with WinRAR.
The resulting file was about 23 MB. I don't know if the 1/3 reduction in size is worth the hassle.