When i right-click on desktop or home screen of Xubuntu, i see considerable delay before the menu appears. Is it normal? Can this be tweaked to bring down the delay like that of other Ubuntu distros or for that matter to Ubuntu's right-click.
SnapOverflow
This seems to be related to application icons.
In Settings -> Desktop, go to the Menus tab, and unselect 'Show application icons in menu' under Desktop Menu.
This should instantly speed it up - you can toggle the setting back and forth and it changes in realtime to compare. I used to have this issue but after unticking it the menu appears instantly if you can live without the icons. They could do with caching them or something I guess.
Incidentally this doesn't affect the Applications menu on the panel. If you use that to launch stuff you could just turn off the entire Applications menu in the desktop menu to achieve the same speedup.
It's normal for the right-click menu to come up slow the first time, but it should be much faster the next time. Until the next computer restart, it should be fast each time after that first time. It is similar to the slowness of Thunar the the first time it is brought up, but responds quickly after that.