Its a classic battle between Toyota and Honda here
It is a tough choice as both are great cars.
The Accord is bigger and more comfy to passengers(especially in the back seat) the Accord will also have the higher resale value(nice to know that you can take a 300,000 mile Accord and use the trade in value for a big down payment on a new car) and there are plenty of parts for it. finding body panels will never be a problem for the Accord
The 2006 and 2007 Accord look good due to the refresh and the squaring of the rear end(that 2003-2005 Accord was to damn rounded for its own good(think 1996 Taurus)
The interior looks great with its radio/climate controls and by 2005 they finally fixed the transmission issues in the auto
Gas mileage is good for all Accord in 2007
http://www.fueleconomy.gov/feg/Find.do? ... 0&id=23569
In fact according to Fueleconomy.gov, the 2.4l auto Accord gets better gas mileage then the 2.4 Vibe Auto and its a bigger car. Of course this is perhaps due to the fact that the Toyota 2.4l is not a very efficient engine mileage wise and also because Toyota is holding on to the notion that this is 1991 and 4 speed auto transmissions are cutting edge

while the Honda is a 5sd auto trans
The Vibe is a great car and Toyota linage makes it a very car (despite the thirsty 2.4l) Gas mileage is not as great with the 2.4l as it should be. The 1.8l engine is very good on fuel but at 120hp that sucker is going to get bogged down with an auto 9especially with the car packed with things and people) Resale value is going to be worse then the Accord due to the Pontiac badging (just like the Geo/Chevy Prizm in the 1990's- early 2000's) Engine parts will be easy to find but body parts(fenders/lights etc) will be harder since that style of Vibe was only made for 2 years (09-10)
The Vibe does have the car seat hooks. There are 3 of them and they are in the cargo area directly behind the rear seatbacks. They are hidden under protective caps
On the one hand the Vibe is good for moving stuff but on the other hand to get a lot of the room you need to sacrifice sitting space for the kids. How many times are you going to be moving a sofa? How many trips or times are you going to be driving the family somewhere?
You cannot go wrong with a Vibe or an Accord. However if it is a choice between an Accord or Vibe, you might be better off with the Accord. Room, comfort and good gas mileage are a good combo
Good luck