Flights from Heathrow to Bangkok can fly as far north as Siberia on the way and they can also fly as far south as the Alps in Europe.
British Airways, Qantas Airways, EVA, and Thai Airways fly from LHR to BKK in just over 11 hours, and the return trip takes about 12 hours 45 minutes.
Yes, operated by Qantas.
Delta uses Heathrow terminal T4.
T3.
There are various places you can fly to from Heathrow Terminal 3 such as Chicago USA, Amman, Oslo and Vancouver Canada. It is an International terminal that help you in your travel destination.
Thomson Airways fly from Terminal 2 to Alicante.
Numerous airlines fly from Heathrow to Austrailia, from different terminals.
Yes
T5.
Delta fly in and out of Terminal 4 at London Heathrow. See related link for more information.
British Airways (BA) typically flies into Terminal 5 at London Heathrow Airport (LHR) from Dublin Airport (DUB). However, it's always best to check your flight details prior to departure, as terminal assignments can change.