rollover effect

[groves]

hi
I am trying to get a roll over effect on my canvas.(this is a virtual
program which will eventually fit into my final program)

Exactly i have a text on my screen and I want to have a brief
discription across it whenever the user takes the mouse on it n hence
giving information about the type of text(event).

Another thign i am looking for is to have a right click on that very
text as well
If somebody can put some light on it, then it would be really great for
my project.
Thank you in advance.