My pet peeve is the Finnish name "Yrjö". It comes from the Greek name "Geôrgios", which means farmer, but nowadays the word "yrjö" means vomit. 'Unique spellings' like some "Everleigh" also drive me crazy.
My own first name Mark, Firstly it is supposed to be spelled Marc as according to my mother I was named after Marc Bolan but they wrote it with a K on the birth certificate. Secondly it just doesn't feel like it suits me, I have no idea what alternative I would pick though. Maybe I just don't feel comfortable being called by my name no matter what it is :)