If you arrive between 7 AM and 10 PM, you can check-in at the VGF lobby. Outside of those hours (or by DME) and you check-in at the GF.
Valet Parking is available at all Deluxe Resorts for $20 per 24 hours. Your DVC card will do nothing for you as far as Valet Parking goes. The TiW will get you free Valet for the purpose of dining only (must show receipt showing TiW discount). If you have a valid handicap tag, the daily valet parking fee is waived.