Firstly, check the fluid level in your M/C. If it's been leaking badly then it should be lower than usual. I doubt it's leaking, sounds like there is either air in the system, the clutch hose is knackered or your M/C or slave cylinder needs rekitting.
First things first, try bleeding the slave cylinder first and see how you go. Get rid of all the air in the system.
Not sure if yours is a verto? I am guessing it is being a rover. It should look like this:
Otherwise it will look something like this:
In the top picture, see that bolt looking thing at the top with a spout in it? Put a rag underneath that to catch the fluid, get your wife to sit in the car, open that bleed nipple by undoing it slightly and get her to push down on the clutch without releasing it. Fluid should come out of it along with air. Do up the nipple again tight, then tell her to get off the pedal. Don't pump the pedal while the bleed nipple is open, that just sucks in air.
In the bottom picture the bleed nipple is on the right side of the slave cylinder.
Rinse and repeat several times until you see clean looking fluid. Do up the nipple tight again. The pedal should feel heavier and engage higher after that.
Don't forget to top up your Master Cylinder.
If this doesn't fix your problem, then it's going to be a bit more complicated....
