Well, my friend works for Northcott disability services in Melbourne and I can personally vouch for the good work they provide! I expect what would be important is making sure they don't spend too much money on administration/overheads and that the money is actually used for the benefit of the people.

I think its really important to find out what charities actually do with the money they recieve. For example, I like to support charities that provide feedback as to what the money they recieved in their last charity drive has been used for. For example, I undertook Movember last year, but didn't get any feedback about what they did with the money I raised for them last year - even if its not that much, I'd still appreciate an email letting me know what they did with the money I begged, borrowed and stole for them.