Optimiser Pro - getting rid of it!

[Busybusybust]

Yes. I am a complete idiot! Within two days of getting a new computer I have managed to download this nasty bit of horribleness. Just wasn't concentrating (too busy watching the puppy's antics).

So, please, (because I am an idiot), could someone give me a blow-by-blow description of how to get rid of it.

New computer is a Lenovo running Windows 8.1.