From its habitus,(general appearance) it looks to be a harmless nursery web spider.

Don't let their larger size intimidate you, they are really gentle giants and won't harm you at all.

This is likely a larger Pisaurina genus or smaller Dolomedes genus.

http://bugguide.net/node/view/2918/bgima...

http://bugguide.net/node/view/1985/bgima...

These are outdoor spiders, so just catch it in a cup (they can be quick) and put it outside, they like trees.

Hard to tell because of the blurry image, but it looks a lot like a yellow sac spider. They are very common. Not especially dangerous but they can deliver more painful bites than most other common spiders. I'd kill or avoid it.

A live one... but from what Joseph said looks like this yellow sac

It's the kind you kill, when in doubt, stomp it out.

Its about the size of a half dollar, maybe a bit larger. It looks to be a tan shade. I'm afraid to get close enough to it to look for markings. Any help would be appreciated.