It depends why you are going to disney and if you are driving.
If you will be spending most of your time at disney itself, and you are not driving, then stay at a resort. The All star types are the cheapest and the price goes up from there. I stayed in Animal Kingdom lodge last time (18 months ago) and will be going back there in 9 months.
If you are doing Universal Studios, consider booking a night at the hotel there. It isnt cheap, but gives you extra queue jump tickets as part of the price.
The first time I went to america was about 12 years ago. Last minute deal, £220 including flights, car and hotel. I know how cheap that seems, but the hotel was shockingly bad. Take your time and look at the facilities and how big the pools at the hotels actually are.