Well, you might have a gift, you see ghosts.
You have to know that they are all around us and there is nothing to be afraid of, they might be trying to communicate with you.
Here are few things you might want to do when seeing them:
Don't panic : ghosts can not harm you, but they can scare you, if you have no reason to be revenged don't be afraid. If a ghost is showing its self to you there is a reason for it and you have to understand it.
Try to communicate: Yes, you might be able to communicate with the spirit. If this is a residual haunting - a kind of recording on the environment - then you probably will not be able to communicate with it. The ghost will not even notice you. That would be like trying to communicate with a video recording; no interaction is possible.
If this is an intelligent haunting, however - a true spirit of a once-living person - you might be able to get a reaction. The spirit might look at you, possibly as intrigued by you as you are of it.
Calmly talk to the spirit, just as if you are talking to a person you just met. Introduce yourself. Ask its name. Be calm and respectful. There is no guarantee that you will get a response, audible or otherwise, but it's worth a try.
By the way, the communication might be the best thing to do.