If I could turn the clock back, I wouldn't be so hung up on schools. In common with many young families, we moved to Dunblane for the schools on the basis of their good reputation, although this was all hearsay and we didn't actually know anyone with children in the schools.
If you want a nice middle class school with 4X4 driving mums, Newton Primary is your place but I would say there is nothing special about what is offered there education or opportunity wise and it can be a cruel place if your child doesn't fit in. Dunblane Primary looks quite run-down compared with Newton and very big, though it has lovely grounds. St Mary's is a very friendly and caring school which is particularly welcoming to additional needs children and has a fantastic nursery.
The curriculum for excellence seems to inhibit learning in all primary schools in Scotland with its emphasis on being a 'confident individual, effective contributor, successful learner and responsible citizen' rather than actually acquiring any knowledge. As a result, many parents in Dunblane use Kip McGrath to fill the gaps in their primary children's learning and some even leave the schools with the great reputations for the private sector.
The high school too has a good reputation based on its results but whether the quality of education on offer is any better than any other school is questionable. They take a lot of placing requests, some from quite far afield, so it could be an option for you when you get to that stage even if you don't live in Dunblane.
For families, Dunblane's real strength is that there are loads of activities going on for kids - sports, music, scouts/guides, boys/girls brigade, the Dunblane Centre and an excellent library. It has a nice safe community feel, the shops and cafes in the town are very friendly and it is a manageable size.
So, yes, it is a nice place to live but I wouldn't downsize just for the schools.