1. Starting from the desk top press [windows key] + [x] then press [p] to open the control panel.
2. Now select performance information and tools
3. Then chose advanced tools
4. At the bottom of this list is the very useful "generate a system health report" tool.
I'll be honest, most of the stuff this report generates will go over peoples head but I like that Microsoft have at least made an effort to demystify the system… I particularly approve of the helpful hints section for dealing with any performance issues a scan detects.
