We are overwhelmed by all the accommodation that is offered and we are not sure where to stay.
Yes, planning a trip to Disney World can be overwhelming. The folks on this website love to share tips and tricks. As with most things in life, there's not going to be a single right answer to your questions. Feel free to ask questions...even ones that seem "dumb" or illogical. We're a pretty friendly bunch.
I honestly can't answer your question, but I did want to say I'd highly recommend staying on property if you can work it into your budget. Especially for a first time trip.
Disney handles all transportation within their network from the Disney Magical Express that takes you from the airport to your hotel, to taking your bags straight from the airplane and putting them in your room. It has a bus to all the parks and Disney Springs from your resort. You will never have to leave the "bubble" and it really feels like a totally different experience. I have done both, and I would stay on property hands down. I don't think I could stay off property again, it just makes the experience for me.
Disney Resorts are great for the reasons you mention (and many more). But, there also are some drawbacks. The biggest one tends to be price. The price of the room and the food at Disney Resorts are usually many times higher than other options. Personally, I almost always stay "off-site" because I get a longer stay at a nicer hotel for less money.
Disney's Magical Express bus service is a great perk. Yet, if you are unlucky you may have to make multiple stops before arriving at your resort. For roughly $80 each way (approximately $105 AUD), you can have a private towncar/SUV take you and your luggage directly from the airport to your hotel. If you're flying from Australia to Orlando without any stopovers, that extra money would probably be worth spending.
http://disneyspringshotels.com/ Good shuttle bus system. Walking distance to Disney Springs. Walking distance to many offsite restaurants and a grocery store (not the cheapest but walkable). Few other groceries a short drive by taxi/uber.
Def look at the Doubletree Suites; roomy recently renovated suites, kitchenette, dining table (they brought us an extra chair as we are 5). Check direct with hotel, via above site or Mousesavers for some good rates.
HopperFan always seems to give good advice. If you're unfamiliar, the Disney Springs Hotels are located on Disney property (adjacent to the Disney Springs shopping area) but are owned and operated by third-party companies. They are a middle ground between the Disney Resorts and off-site hotels. While they don't offer the Disney perks, they do provide continuous transportation to the theme parks. Many off-site hotels only have 2 or 3 trips in the morning and 2 or 3 returns each evening. The Disney Springs Hotels have service every 30 minutes all day long. If something comes up one day and you want to return to your hotel, it's very easy.
I am a big fan of the DoubleTree Suites. Each suite has two queen beds and sleeper sofa. They are 540 sq feet (165 sq meters), which is twice size of one of Disney's Value Resort rooms.
Although you won't have two distinct rooms, I believe the tower rooms at the B Resort have two queen beds and a single sleeper chair. That might work, as well.
This is a Bing Map I created for an old thread. It shows the seven hotels in relation to Disney Springs.
Link to Interactive Map:
https://binged.it/2nVqbwk
On the upper-right corner you will see Crossroads. Crossroads is a shopping area just off Disney property. There are a bunch of fast food and casual restaurants, including some open 24 hours. You'll also find the (expensive) grocery store that
HopperFan mentioned. I like the Doubletree Suites location because it's an easy walk to Crossroads. That gives you so many more food options...and virtually all of them are cheaper than what you'll pay for equivalent meals on Disney property. Plus, you can also go to Disney Springs.
That's my take on things. Feel free to ask questions.