Suites are much more expensive (except for All Star Music Family Suites and BWI Garden Suites) and are located at the deluxe resorts and come with club level services. No villas (other than a few at Animal Kingdom Lodge) come with club level services.
Suites do not have washer/dryer (I guess the rich can afford to send everything out) and generally do not have a full kitchen, but rather a butler's pantry-style kitchen (although some of the Presidential and Vice Presidential suites are exceptions to this). The room draperies, furnishings, bedding, and appointments are superior in the suites (marble baths, etc.). Google Disneyworld suites if you want to see some pictures.
Suites (except for ASMuFS and the Garden Suites) are never discounted, but villas can often be had on public discounts.
We were upgraded once to a two-bedroom suite at BWI. It was gorgeous, with three balconies, a separate living room/dining area and three huge marble bathrooms. The price was something like $1,500 per night.