Place ribs in large skillet. Cover with salted water and bring to a boil. Reduce heat and simmer over low for 1 hour, or until meat is tender, but not quite falling off the bone. Remove from heat and drain.
Add olive oil to a sauce pan and saute the onion and garlic until the onion is tender. Remove from heat. In a blender, combine 1 cup water, vinegar, ketchup, barbeque sauce and lemon juice. Season with salt and pepper and pour in the melted butter mixture. Puree for 1 minute, then pour back in saucepan. Bring to a boil, then remove form heat.
Place the boiled ribs in a shallow baking dish and pour sauce all over them. Place in refrigerator for at least 2 hours to marinate.
To Freeze: Freeze in the marinade.
To Reheat: Barbecue ribs on an outdoor grill over moderately hot coals, basting with the sauce and turning often until well browned.