(T) Problems and warrenty...please heeeeeeelp!

As people may know on here, I've not had my Cinq very long, about 3 months. It's still covered under warrenty and there's still stuff going wrong with it even though I've taken it back to them about three times and some of the stuff listed below has supposedly been sorted by them already!

I just want my car working properly. I paid them the money for the car fair an square and so far all I have had is problems with it and then when I've asked them to fix the problems they've had it in all day (and I have to get the train to work) and then the problems blatentley hav'nt been sorted!

A small list:

+ Brakes: Front brakes squeek even though they've had them off, given them a clean etc.. and set them up once already.

+ Head Gasket? After reading the things written by Fixitagaintommorrow about head gasket's I'm paranoid know about oil I keep spotting around the cylinder head (I think it's called that!). I've cleaned it off once and it's reappeared again a week later.

+ Rear Suspension: Creaks and knocking noises whenever I go around a corner, could it be the bushes?

+ Rattling noise under bonnet: I think it may be the heatshield? Someone elsr described the same sort of noise on here. It rattles when going slow (20 mph) and happened the other day quite badly when reversing.

+ Engine mounts: Clunks quite badly when accelerating hard (not that I EVER accelerate hard!).

+ Heaters: Front left heater inside the car doesnt work and my girlfriend keeps getting cold!

+ Squeling: When cold on idle the engine squeels badly, maybe the fan belt or timing belt (or are they the same thing??)

If anyone has any advice on what the problems could be (please correct me if you think it could be any thing different because I know next to nothing about cars and engines) I need to describe what the problems are to the garage because otherwise they will just take the pi$$ (...again!)