Several problems - Taurus 2000 SE Vulcan - advice appreciated

I have several questions problems on my 2000 Taurus SE (Vulcan with 46000km) that I'd like to get your opinion on please.

1) Brakes:

My front brakes are screeching a bit when I apply them, although they still work well. How much longer can I use them before I should replace them? The front hub caps look like they are covered in a dust - from the brake pads?

The car judders ever so slightly when I use the brakes at speed - not enough that I'm worried and have to rush to get them fixed. But enough I presume they need attending to in the coming weeks / months.

Also, when I am stationary and release the brakes, there's a loud clunk. I can't describe it better than that, but it seems to occur when I apply and release the brakes when stationary.

2) Heater / Air Conditioner

I'm hearing two noises when I turn the heater onto level 1 (lowest output), set the temperature to cold and set the air to come out of the front passengers vents. The first sound is like rustling paper, and the second is a bit like gurgling water. Is this a problem, or the first sign of a future problem?

3) Engine / exhaust

The car is not performing well at all. Fuel efficiency is poor and performance is poor. I do a lot of city driving, typically at 40-50km/h. At these speeds, if I hold the accelerator pedal steady at a constant speed, the revs will suddenly drop, or the engine will suddenly seem to clog. The speed drops so I have to accelerate a bit to maintain my speed. When I press the accelerator, sometimes the car will shoot forward but sometimes nothing will happen, so I have to keep pressing until something works. It's almost as though it's mixing the air and fuel wrong and it's choking.

This happens when I pull away from a standing start. When I press the accelerator, sometimes the engine pulls well but mostly it does nothing, so I have to keep pressing. But even though I press the accelerator more and more, I don't get any more acceleration.

The engine seems to hesitate when cruising or accelerating as well. The engine light isn't showing. The dealership fixed the car a few weeks ago when the symptoms were much worse. The week after they did the repairs, the car ran fairly smoothly, but things are gradually worsening as time goes by.

4) Accelerator pedal

I can feel vibrations from the car through the accelerator pedal. For example, I had the wipers on this morning through heavy rain, and each time the wipers stated their cycle, I felt a thump through the pedal. I can also feel other vibrations, though not from the road. Is this something relatively small?

Any advice or comment greatly appreciated!

Stodge, You are hearing the metal warning minders on the front brake pads touching the rotor. Delaying service will likely cost you a set of rotors and pads if the rotors aren't already scored.

Ok - thanks for the warning.

also you could check the pads, because somtimes the pads just squeak , and the only way to get pads that don't squeak are to buy new ones that are the more expensive anti squeak pads, about double the cost, but for how often you need to replace them it's not that muuch of a difference in price, the shuddering that you described when you apply trhe brakes is most likely just some warped rotors, this happens when you come to a sudden stop and hold the brakes on, not only does it keep this area of the disc hotter, but it is possible with the amount of pressure you are holding on them that they will slightly warp, all you need to do for this is take them off and take them toy a local shop, and that will resurface them for a small fee, soming like 10 dollars each, then that sould fix that problem, about your Climate control suystem it is possible that there may be some debris in the system, I'm not really sure but it is a possibility

Has this car had its tuneup yet? What did the mechanic do the last time he worked on it? Your mechanic should be able to hook up your car to a scanner and see if its getting enough fuel and spark and could also check your exhaust system for any restriction. Man does it sound like your muffler got crushed or something but that should have turned on the SES light. Does your ehaust smell funny like sulfer or gas?
On the Temp control issue its most likely leaves have gotten into the air ducts and your hearing that. Also might wanna make sure the drain hole on your air box isnt clogged because u might have standing water in thier that your hearing. One question on that is do u keep the thing on max air all the time or normal?