Have never been to the O2 s can't help you on seating plans but have heard it's a fantastic venue and I believe the catering etc is really good.
The Docklands Travelodge might be in Tower Hamlets (and there's actually not much wrong with T Hamlets) but it's actually in Docklands itself which is basically a business area. The only thing there is offices so I wouldn't worry about that. If you're going at the weekend , there's not many people around at all If you're going during the week its full of people coming and going to work.
The shops are all pretty good round there too btw.
DLR is included in e.g. Tube travelcards and oyster cards if that's what you mean.
The 02 is fabulous (make sure you leave some time before the show to look around properly - go to the chill out zone or the ice rink). The top tier seating is quite high up, but you will have a great view!
I lived in Docklands for years and you will be fine
OK, you'll be able to use the same ticket for the DLR as for the tube and overground - as long as it's a travelcard, which I'm presuming is what you'll be getting
If DD is really scared, let the stewards know - I have two friends who on separate occasions have asked to move from the top tier as they didn't like it - they we're moved after really playing up how scared they were though...
It won't all be a disater! I am v you are going Relax, the evening will be fiiiiine, and great fun.
Don't worry. the O2 is a great venue and I am sure your DD will love it.
The Travelodge is actually on the edges of the docklands business district (and very close to East India DLR). (Tower Hamlets is the London Borough). Its a decent area and you will have a great time. If you are there with time in hand take the DLR up to Cabot Square and Herons Quay and have a walk around. Its all quite smart and at weekends there are often music or other events on which attract a lot of families.
DLR is a separate ticket as far as I know. However you just buy a ticket at the station from the machines.
I am assuming you are coming in from outside London. Ask for a tube map (free) at the tube station ticket office when you first enter the system. That should show DLR lines too. If it doesn't the the main tube/DLR intersections are Bank and Tower Gateway. You can also look on the tfl website which has various maps.
We did a City Cruise last week and it was fab. We went from the London Eye to the Tower, and it is about £6 for adults - and you can sometimes download 2for1 vouchers from the National Rail website. We did Kensington Palace as well...it was...meh. Lots of stuff about the "Last Debutantes", a bit boring, but there are a few nice gowns on display.
Lastminute.com has lots of great deals, so check it out.
It will be fine and fun! Tower Hamlets is a huge area within which there are pockets of dodginess but Docklands is not one of them. O2 is a very impressive venue and will be v exciting to go at night when it's all lit up. Great public transport links too.
Tate Modern great and all along the South Bank (where Tate Modern is) is well worth visiting. You could get tube to St Pauls - look at the outside of the cathedral, then cross the millennium bridge to Tate Modern, then walk down to Houses of Parliament, checking out all the street artists, groovy things at the National Theatre, Gabriel's Wharf (eclectic shops) along the way.
Also if you are arriving in London by train check out Days out guide which gets you 2for1 entry into loads of places including the aquarium and the zoo.
You will be just across the river, about 5 stops on the DLR, from Greenwich which has a nice market on the weekends. You can get food there and there is also a Sushi bar with a moving belt which is a big hit with DD aged 6. Greenwich has the park and Royal Observatory. If it's wet go to the Royal Naval College, now part of Greenwich University and go into the painted hall (free) the ceiling paintings are pretty interesting. There is currently a small version of the London Eye there. Just don't go if it's extremely windy, as I learnt to my dismay.
The DLR is part of London transport so a 1 day travel card (get zones 1 and 2) will cover the DLR, trains busses and underground. If you go to the Tate Modern, wander down to Borough Market (Friday and Saturday) Buy a smoothie there for lunch and fill up with tasters from all the stalls. It does get quite busy but is a bit of an experience.
The docklands travelodge is very nice but a bit of a walk from the DLR (London City) but it shouldn't take more than about 10 minutes as the DLR station is inside the airport iyswim. The travlodge right next to a storage unit (Shurguard storage) so you can't miss it. Walk down the road, cross over and the travelodge will be on your left.
I'd personally buy an oystercard, which is a pre-paid travelcard, put about £8-10 on it and that will see you through or just get a day travelcard as other people have said. There should be someone at the station to point you in the right direction (TfL staff!). Dependng on the age of your dd, you might need to buy one for her.
I don't know about the top tier of the O2 (I was sat lower down to see Darcey Bussell/Katherine Jenkins earlier this year, but the O2 is a really nice venue.