Just a bit of wisdom I have acquired, thought it might be of assistance to other android users.
I have 3 android devices, HTC Desire, Asus Transformer, and a Slatepad. Occasionally, due to my love of free apps and "gentleman interest" websites, things go a bit Pete Tong and stuff goes nasty.
This will restore an Android OS device to exactly how it came from the factory, use wisely, and back up often.
With the device off, and preferably plugged in to AC charger, hold down the volume key. Then hold down the power key. You will be greeting with an old school BIOS style screen.
This is its recovery mode. Use the volume keys to navigate, and power to accept selection.
Hurry up and wait.
Update the OS, and get yourself on Marketplace to fill it with more nonsense. Good as new.
Enjoy.