Let it go, Victoria. Its not worth your energy and time trying to salvage a 6 year old machine. Hardware begins to fail in all sorts of areas, you fix one thing and something else will start to fail in time. You're best option is to purchase a new machine. Even a budget machine by todays standards would surpass your current machine by a large margin.

If you have a budget (and give me an idea of what you'll be using it for) ill post the parts and prices here for you.