Martin,
Unfortunately, what you see in the Print window is all the options available. You can print description for only the icon, for all controls, or for connected controls. You cannot select to print description of only few controls. However, I tested this and was able to print description for a waveform chart.
You can suggest this additional feature if you go to ni.com, click on "Contact NI" in the top right corner, and then select "feedback" under Product Feedback.
Our R&D engineers will review the suggestion for a future release of LabVIEW.
Zvezdana S.
National Instruments