Opinions on what to do with my car

I have a 2001 Ford Taurus SE with 206,000 miles on it. The steering rack and pinion is bad, Both Ball joints need to be replaced, Both CV boots need to be replaced, Both front struts and springs need to be replaced, Brakes and wheel stud need to be replaced, Plus it has an oil leak and transmission leak and for some reason the tempature gauge fluctuates between middle and cold and the heat barely works. Should I just junk it and get a new car or get everything replaced on it? I have no credit and I pay 250 for just liability on this car. Opinions?

2000 Ford Taurus SE Wagon Heater Problem?

The heater doesn't work. We flushed the heater core hoses with coolant and they are not clogged, what is the reason for the heater not working?

Added (1). The heater works, just very very light.

Will these tires fit?

I have a 1999 Ford Taurus that has 205/65R15 tires on them. I'm looking to replace them and a friend of mine has a set of 205/70R15. Will those tires fit on my Taurus

How look to put in a new engine?

I'm having a new engine put into my 2009 Ford Taurus Limited. I was seeing someone could give a rough estimate of how long it would usually take to take out the old engine and put in the new one. I just want a rough estimate of how long and if the process is a lot more complex than I'm thinking