Heathrow to London with toddlers

Any of the three would be a good idea.

For a private car, look at Just Airports limo service.

For a bus, you would go to the Heathrow bus terminal, attached to the airport. There are signs directing you to it when you get off your flight and begin walking into the terminal. You simply approach the ticket window and buy your tickets. Inexpensive. This bus will deliver you to Victoria Coach Station in central London. It is right across the street from Victoria Station where many trains and tube (underground, subway) lines come through. You can get a taxi from the coach (bus) station to your hotel or apartment.

The third option is the taxi all the way in from the airport. A taxi will take you right to the door of your hotel or apartment, of course, which may be good for sleeping children! I can give you the name (by Private Message) of a very good taxi driver we used in London. We used him for a number of trips. He usually could be found in the taxi rank outside our hotel. We stayed at an expensive hotel last time where a lot of insurance business travelers stay, so I'm sure that was a very profitable location for him! He gave us his business card, email address, and we are friends with him on Facebook. Will be glad to pass this on to you so you can contact him and make arrangements for him to pick you up. It is a non-smoking cab, and he does accept Visa and Mastercard. (Not all cabbies do.)

Or just take the Heathrow Express.

Thank you for the information! I forgot to add that there will be 5 of us, including our 10-year old. Justairports just seems to accommodate 4, but not 5, people.

Claudia's suggestion is excellent. A very good idea; fast, too.

A taxi will accommodate 5.

Heathrow Connect:
https://www.londontoolkit.com/travel/heathrow_connect_train.htm

Blackberry Cars are recommended on another forum:
http://www.blackberrycars.com

To add to my succinct answer the neighborhood where you'll be staying might help you make your choice.

The quickest ( 15 minute ride) albeit most expensive option is the clean, comfortable Heathrow Express. The Connect is also a great option. Both go to Paddington Station. Will you be staying near Paddington.

Again, if you know where you are staying it might help you make a decision on the best means of transport to get there.

We are deciding between a hotel near Paddington station- which it sounds like the heathrow express is the best choice- and near King's Cross station.

If using the express check out the various discounted fare options through buying before arrival.

Yes, as Marco points out, definitely look online for discounted tickets for the Express if that's the way you choose to arrive in London.

I thoroughly enjoy the Bayswater neighborhood, thus my preference to use the Express. Also has to do with flying the red eye and simply wanting to get into London to start my vacation as quickly as possible.

Great city. Enjoy your stay.

Heathrow Express gets you to Paddington Station. Depending on where a hotel in the Paddington area actually is located, you may still want a cab to get there. Especially if the weather is bad and you don't feel like trooping around with the kids and the luggage searching for your hotel. Crossing from Paddington to Kings Cross by taxi may take 30-40 minutes or so.

The most convenient way is sure to be by car directly from the airport. Assuming that's Heathrow, I'd be surprised if JustAirports can not provide a van. Call or email them. Check the heathrow.com site for other car service or taxi options.

I decided to reserve a private through Blackberry cars. They were very responsive and gave a fair rate. Thank you for all of your input.