Welcome to FT!
Not to be mean, but your question is somewhat ridiculous.
I mean, if I ask you for a good place to stay in the UK, what would you say? We need to know things like:
1) How much you are willing to spend.
2) How much you *want* to spend.
3) What you will be doing while you are here.
4) What type of hotel style you prefer.
5) What type of neighborhood you prefer, etc. etc. etc. etc.
As for the rental car question, I do find that the rates at the Hertz local edition (HLE) on the upper west side, for instance, are often cheaper than renting at LGA. YMMV though.