Dell Inspiron 1526 going crazy!

I bought a Dell Inspiron 1526 in June of 08' and for the first month it is fine, the second and third month it shows signs of problems but I ignored it since I thought I was causing it and ran through Control Panel (Cleared all Cache, Temp Files and Data and Set everything to Default), Bios Settings, Diagnostics and Anti-Virus Software. Even I downloaded CCleaner and nothing would fix it, and for the Fourth and Fifth Month thigs are getting worser and worser...

Problems:

~Overheating and Slowing Down and Programs Keep On Freezing.

~Can only run I.E., DWM.exe and Explorer.exe at same time or you know it freeze-up!

~Mouse going crazy (moving around, sometimes opening a lot of programs without I wanting to open it and jams up) if doing things a little faster.

~Giving me sickness, dry throat, dry face, dry hands and dry feet, also develops acne for some reason, tried out other Inspiron 1525 and 1526, same thing.

But, I would want to replace it, my father refuses and I would have to deal with it...

I don't know what is going on but I hope someone in this very section could help...

Went to the Doctor and Doctor is saying I have mental illness and wants to put me in a hospital...