Nail or no nail?

I've had my car for nearly six and a half years of it's seven-year life. And now I'm at that crucial stage in a motor's life when things start to go wrong. Big things. And all at the same time.

In truth, nothing major has gone wrong yet and since I've had the car it's been fantastic in the reliability, bits-not-falling-off department. However, the old girl has recently been giving me a few clues that indicate that some serious failures are not too far off. For example, when turning my steering wheel full lock to the right, I get a sort of metallic grumbling sound. Sometimes when I put my heater blower on, one of my speakers makes a fizzing sounds. The same speaker fizzes on occasion when the heated rear window is activated. Also, the number of creaks and squeaks seems to increase on a daily basis. My car appears to have developed arthritis along with irritable bowel syndrome, rickets, scurvy and manky hip. Oh and my gear linkage needs replacing soon or else I won't be able to change gear from 1st to 2nd. Or 2nd to 3rd. Or 3rd to 2nd. Or 2nd to 1st.

So I'm now in that quandary of quandaries. Do I spend some fairly serious cash on getting my car back to full health or spend some very serious cash (which I don't have - "oh hello Mr Car Finance") and buy a new(er) one? Hmmmm. Or should I just set fire to it and push it over a cliff into the sea?

Answers on a postcard.