PS (09-24-2015): booked Westin Lake Las Vegas via BA Avios points. It cost about 11,000 points for the premium room ($81 + taxes). The room there starts at 7,000 SPG points, note 7,000 points is for traditional room (I got a premier double room). I feel it’s a decent deal as SPG points are usually worth more.
PS2 (09-25-2015): more hotels booking. Last night I also booked Hilton Anaheim both via BA Avois (about 18,000 points) and Chase Ultimate Rewards (about 10,500 points). The hotel was very close to Disneyland. And today I booked one more night Hilton Anaheim via Chase UR (now we have 3 nights total), it seems the UR points for the hotel increased overnight, but the dollar price stayed the same. The next step is to get the Disneyland (and California Adventure) tickets booked.
Other nearby hotels, both cost HHonors 20,000 points : Double Tree Anaheim (this one does not have free breakfast, parking cost is similar to the Hilton above, about $16 per day).
Another one: Hampton Inn Los Angeles-Orange County-Cypress. Hampton Inn has free parking and breakfast compared to Double Tree. It’s a bit farther away from Disneyland.