...should i give my recruitment agency that i want to leave the job i'm in? out of courtesy i'm talking rather than reality, as i could run off today if i wanted . . . hang on . . . i do!
I would give them as much as you can and ensure you don't take the Mick during the notice period either. People only don't give/work their notice out of cowardice in the main - be dignified, explain the circumstances, set the date and get back to work.
Having had to eat humble pie in order to put food on the table for the family, I can tell you it is something I would never wish upon anyone.