From Rick's London 2014 book & the forums it appears that there is an express train from Heathrow to Paddington (we are staying a block from Paddington) but it is not covered on any passes and it is a bit pricey. Purchasing an Oystercard with 7-day Travelcard option will not get us the 2-4-1 deals as you have to buy the travelcards at national rail stations. The stations at Heathrow for express trains (not Tube) do NOT sell those passes apparently, but we could buy them at Paddington upon arrival into downtown London. So the question is, what is the best/cheapest way to get into London and purchase those 2-4-1 deal Travelcards? Also, the rail Travelcards have no way to extend the zones as the Oyster cards, which can be loaded with extra credit for extensions beyond the Zone 1-2 if you opt NOT to buy the Zone 6 range cards). Since we are planning trips to Hampton Court & Greenwich, it may be better to pay the extra and buy a Travelcard at a National Rail station for all zones (eliminating the problem of not having an Oyster card with extra funds on it) and bite the bullet and pay for the express train from Heathrow to Paddington out of pocket.
This is all quite confusing, but if anyone has any better suggestions, I'd welcome hearing them.