Hi Sue, I always stay at the Thistle, very clean, delicious food in restaurant, friendly staff, reasonable cost, large first floor patio to watch the planes. AND. for £5 there is the Pod to take you across to T5. The advantage of the Pod is that it runs all the time. You are not restricted to the times that a hotel runs a coach.
The Pod is a driverless cabin that takes 4-6 plus luggage and runs on a monorail. Fun as well as convenient.
Enjoy your holiday.