From London to Manila I would opt for Catahy-Pacific which I try to fly whenever possible, barring that, China Air but hopping at the hub in Tapei is a real pain with their very stringent security. Cathay is great and usually runs just over 1000 British R/T.
There are only 3 International Airports in the Philippines (Manila, Cebu, and Davao). I would go for Manila and then transfer onto Cebu-Pacific for domestic travel. Domestic and international are 2 separate airports in Manila but the airlines provide courtesy vans to shuttle you for free between the 2. NEVER take a taxi if you can help it because the obligatory Foreigner Tax is the worst of any nation in SE Asia bar none. Avis rents cars with drivers for a bit over 800 Pesos for I believe 3 hours (Pesos is currently at a bit over 44 per US Dollar), but 800 is an actual fortune for most Filipinos so be careful.
If you are thinking of beaches, most foreigners head for Borocay, but that seems to me be self defeating since it is entirely geared for tourism, way over-priced for the country, and there are literally hundreds of very unspoiled beaches and much lower prices to boot.
Unfortunately if you go before December you will be in the midst of Monsoon (which I love but will be hell for you if you are looking for sand and surf.
If not Borocay, which beach? Mactan Island is great, off of Cebu, Shangri-La is very nice. Places to NEVER go, Palawan Island and Mindanao and any points south of Mindanao (Mindanao Province actually includes Basilan, Sulu, and Jolo). Palawan and Mindanao on south are home to 7 insurrections although Palawan ebbs and flows and is really only home to 2 of them. I usually live on Mindanao when my wife is not in school here in Cebu.
If Mactan is not what you are looking for you might consider Bohol, which aside from great and inexpensive beaches has the "Chocolate Hills" and a great little primate called a "Taysir" which looks just like a Lemur.
As for other things to do, I could recommend soemt hings but would need dates and locations. There are literally 7,107 islands here with a multitude of ethnicities. Each village has its own "Fiesta" for its patron saint, and then there are others as well, especially tribal celebrations.