My Macbook (mid 2007) was having difficulty charging; a problem I first attributed to the charger. After buying a new charger the problem was only some what improved; so having a $10 coupon from I fix it I decided to try a new MagSafe board.
Changing the board was easy thanks to the iFixit guide. I replaced the LCD panel in this Macbook once before (also from iFixit) and this project was super easy in comparison. Snapping the board into place took a bit of force and made me nervous.
Cheap and simple fix. The rubber insulating the face of the old board had warn away and I think the charger was shorting on it.
It helped having gone into the Macbook before. Make sure to have something on hand to keep screws sorted by steps and it's good to take notes.