I agree with SwissTony. The airport area is bleak and the hotels are not meant for long stays. The nicest I've seen is Bristol Place. But you can take the airport express to downtown hotels and back for a reasonable fare direct from either terminal. Rather low Priceline bids for 4* hotels have been every effective for the Toronto downtown and the airport zones or check out Hotwire. Another problem with airport hotels is - no surprise - airplane noise.