A son of a friend of mine, Windows machine went down.
I had ordered a new operating sytem with KDE.
I couldn't wait to show off KDE.
However,the OS didn't come in on time, so, I installed something for the meantime.
I thought it had some version of KDE, but it didn't.
It came with an older version of Xfce (4.3) supporting right click menu.
Now, that the CD came, I have trouble convincing him to switch.
His mom said, "now, he won't let anyone near that computer."
The 13yr old explained, the right-click thing is addictive.
He finds it a cinch to use.
He refuses to try anything else!
I'll try...but, wait, "I got KDE."
He'll ask, "does it come with right-click menu support?"
"...KDE can place all your pictures (any format) on the desktop and it's the most configurable. It has the world's best looking wallpaper. It's less virus prone than any desktop out there, and it supports multi-touch screen."
He'll repeat, again .... Can you blame him? What's your opinion?

Not just an application,but the entire desktop main menu?

It already is : right-click the desktop -> Desktop Activity Settings -> Mouse Actions -> set right-button to 'Application Launcher'.
Apply and that's it! I hope that is what he was looking for...

please note: I am using a release candidate of KDE 4.4 SC so this might not be possible in previous versions but it probably is.

For al the stupid people like me that cannot change back to the standard menu, you can acces Desktop Settings by clicking the cashew.

edit: to late

prince wrote:Not just an application,but the entire desktop main menu?

It looks like this on my system. Is this what you need?

Yes!

Well, it'll be available in KDE SC 4.4.

Hans wrote:Well, it'll be available in KDE SC 4.4.

Thanks. Right-clicking is good!

A warm thank you from us all; son, mother, and dear friend. Thank You!

Alec wrote:

I removed the scrolling-switches-desktops entry. Scrolling still switches desktops. How useful is "right click (Main Menu)" thing if it doesn't work?

You don't give us much chance to help you; do you even want help? If it doesn't work it can be fixed so maybe it's already been fixed in newer version (it's always worked for me though). Which version of Plasma Desktop do you use? Do you use multiple activities? Which desktop type(s)?