Woohoo! another religion thread. There was a 'Catholic Q & A' tread just for this purpose but I will answer your questions.
Jesus honored his mother and hence so do we. If Jesus deems a person worthy of honor, that person is worthy of honor.
If you have a Mama, you should know how Jesus felt about his. You can screw with a person, but you never screw with their Mama.
An false idol is when you worship the thing. The medals statues and what not are basically just prayers. It's easier to keep your mind on the prize when you have a representation. It's nothing more than that. A statue or medal cannot do shit.
It's not an easy process, but technically we are all saints until proven different. A saint is a person who is revealed divinely to be in heaven, by way of intercessory miracles, that are verifiable and proven. It's a long process. In the bible Paul often refers to saints dead and alive, so technically yes.
Saints aren't needed, but they serve as examples of a Christ like existence in a fallible person.
To be clear we don't pray to saints, we ask saints, who are in a state of grace for prayer and intercession. It's just like asking anybody else for prayer except they are in the light of Christ and are closer to God than we. You never have to use them ever, it's just another 'tool' of prayer.