SemiLiveMusic,

Try the ComboFix, it might save You from reinstalling everything on Your laptop.

As for the power supply, they all get hot to a some degree, but if they are too hot (You get uncomfortable while holding firmly in Your hand) that means laptop is drawing as much power from the adapter as it can (i.e. power supply is overloaded). Try to find the original power requirements for Your laptop (usually written on the back of the laptop and adapter, or in specifications sheet) and compare it with the values on Your current power supply. The important numbers are those designating voltage (V) and Amperage (A) they should be the same, or as close as possible.

Using incorrect power supply put additional stress to all the components, and can cause problems with hard disc (or any other component with high power consumption), but it's not necessarily the cause of the problem in Your case.

Also, it is not necessary to buy original power supply adapter (usually they are ridiculously expensive) even some 'no name' replacement will be as good as original if it gives the same power output.