While I know others may disagree with this and its not the best solution tuneup utilities works great for us. It shows you the problem offers to fix it or you can fix it, it gives you a simple registry editor if you not good at editing registries and helps to optimize the settings in the pc. While it does have the "and it harm none addative" we have seen it try to do some pretty weird things. But over all for an easy to use program that will help with simple analysis I would say try this if it doesnt work for you, you can always try something else.
But actually knowing what you are doing is the best trouble shooting out there.I myself haven't seen anything better than knowledge for repairing computers.software won't help when it is hardware or drivers or BIOS or conflicts.tuning one up is what you do after you get the machine running right.when you are trouble shooting a machine look for the cause not the solution.