I'll be arriving at Heatrow on the morning of the 17th. I had planned on renting a car for my stay but would like to see if it may be best to just pick a Hotel close to any train station that services Heathrow and only rent the car for the days in the countryside. Any thoughts on this would be appreciated.
If you're talking about the cost then its impossible to say without knowing where youre going. I would imagine that the train will always be cheaper in the end, because as well as the car hire cost you will also have to pay the congestion charge when you come in and out of london, petrol and parking costs.
But of course sitting on a train isnt as nice as a drive in the country... so maybe you will prefer driving anyway.
If you want a hotel near a train station that goes to heathrow then you either need to be near paddington (for the heathrow express, which is an expensive overground train), or anywhere along the piccadilly line (underground train). That will include stations like piccadilly circus, leicester square, covent garden