I've dove there all year round and can say that anytime of the year is fine - it's more that you have to be aware of what time of the day the currents will be running. This time of year the currents get pretty rough by mid afternoon on some of the sites.
there are a couple resorts there to choose from. Here's a list to get you started: Aquaventure, Planet Dive, Club Ocellaris, Balai, Solana, Eagle Point, Mayumi, Dive 7000, Vistamar, SM resort,....The first two are preferences of mine.
Bahura and Twin Rocks are two of my favourite dives down there. Pani's Point is great for macro, Sombrero and Beatrice are also nice.
The water was around 26C this January. That's ~2C colder than right now.
edit: btw Anilao is a topic that has come up many times before. A quick search will yield plenty of info.