From the Anaheim Amtrak station, its only a couple of miles. Take a taxi, it should be around $10, a little more if you hit a lot of red lights. If you didn't have luggage, you could potentially walk it ...
To John Wayne there are shuttles, most recommend SuperShuttle if you have 1 or 2 people. With as many people as you're transporting, you're proabably better off taking a taxi (well, 2) which will be ~$50 including tip. I think the VGC is one of those hotels that negotiated a flat rate with the taxi companies but can't remember ...
Yes they have negotiated a flat rate. Go to the concierge in the main lobby and ask about a cab coupon/voucher. They will give you a coupon to hand to the taxi driver. It was a really good deal. I can't remember the exact amount though. This was in early September so I'm pretty sure they are still doing it.