Yeah, that would be the way to go if I wanted to extend the life of this 2007 computer. But, the display's also not in great shape (mostly evident in the white screens on bootup) and I really do want an updated GPU so I can get back to gaming on it..
Do you have grey spots in the corners? My 2006 20" has one in the lower left, and a small one on the upper right. Not too noticeable unless you have a solid bright thing full screen (since windows normally don't go down there due to the dock, and the spotlight icon being on the other side), but they've been there for years a long time without worsening, and I never understood what caused it. I even tried "massaging" the area as suggested somewhere, but it neither improved nor worsened. Kind of looks like some backlight issue or something.