There is no deleting for frames, but you can hide them. Tables can be deleted, or wiped, however.

thanks guys

so when i open the addon's window (frame) the lua draws the elements into and when i close the garbage collector collects them so next time i open that the elements won't be drawn on each other cause a mass but because the garbage collector the last elements deleted by the GC and i can draw new elements in a clear frame?

Actually I think you can remove frames if they were created from LUA code.  When you want to remove it, just call frame:Hide() on it and then set it to nil.  Then just call the garbage collector.

Example:

local MyFrame = CreateFrame("Frame", "MyFrameName", UIparent)

MyFrame:Hide()

MyFrame = nil

collectgarbage()

I currently use this in one of my addons.  I monitored memory usage and without the collectgarbage() call, memory usage keeps building up.  Use it and your frame is collected by the garbage collector

thank you so much KC !