Hello Sidhart,
GO ahead with the proposed marriage, if you like her.
Blood groups do not determine possibility of disability for your future child.
If you marry a girl with any negative( A-ve. B-ve,AB-ve or O-ve ) blood group and your first child is positive blood group, then there is possibility of disease to your second child. But this can be prevented by proper treatment after first pregnancy.
About the ' cases before where, when the child is around 10 years these defects and disabilities come out' that you mention , did this occur in your relatives?
In that case some genetic disease is a possibility ( unrelated to blood group ) and you may get an opinion from a clinical geneticist.

Always better to avoid consanguineous marriage ( marriage with blood relatives)

Hi Siddhart
As such your baby will not face any problem in the future. The problem comes if your are O Positive and the girl is O negative. This forms a mismatch in the Blood Groups (as can be also possible in the other blood groups) and can lead to problems for the baby.
I would say that you give a Yes for the marriage.
Regards
Take care

1. good news is that you both are Rh+, problem would have been if she was Rh-ve, then one might have to consult for Erythroblastosis foetalis.
2. If you still want to be sure, consult a pedigree analyst.

Hello!
You can of course marriage with a o+ girl. There is no harm at all of being o+ and to marry the same blood group. Your baby will not have any disability . The disability or any health issues of a child in future depends upon the hereditary condition, auto immune disease, the environmental factors. Yes if the male partner id Rh+ve and female partner is Rh-ve then there is chance of problems in child otherwise not.