One actor who's name isn't really "bad" or noteworthy but has always bothered me is Brit Ralph (pronounced RAFE) Fiennes. "RAFE"? What's up with that? It's like pronouncing Herbert "HER-BARE". Perhaps it's legitimate, but it just seems pretentious and self-important. I mean really, if you don't want to be called RALPH just change your name completely and be done with it.
I think that pronouncing "Ralph" as "Rafe" is common in the UK. His name is one I considered putting on my list, as both the first and second name are difficult, but I like the sound of the overall name.
That name is one of a small number of UK first names that are pronounced differently or are hard to pronounce in the U.S., like St. John and my aforementioned Ioan.
Having watched Chinese cinema of various stripes for now on sixteen years, and having most of the related film books that have been published so far, I have to say that the regional variations of Chinese names can often play havoc with how those names appear in transliterated English credits on Chinese films. Obviously, the Chinese characters remain consistent, which is only right when one considers that the majority of people who see the films will likely read the Chinese characters.
The problem (small as it is) for people outside the Asian community has been cataloguing and writing about Chinese pictures while keeping a consistent naming convention, particularly after the '97 HK handover, at which point several films started appearing with actors credited (in English) by their mandarin transliterations after years of being identified (at least on HK DVD packaging and film credits) by their Cantonese transliterations. I still see this trend on the occasional DVD cover. Sometimes it makes sense, particularly if the actor is of such origin to warrant it, but many times I know for a fact the actors are Hong Kong Cantonese, sometimes even descended from long lines of Hong Kong Cantonese, but now all of the sudden they're names are being transliterated in the Mandarin style, almost as if there's a deliberate attempt to satiate the newly opened mainland market demographic.
As far as the western coverage goes, there's more consistency today than there was in the early days of Asian cinema awareness, when books like Thomas Weisser's execrable ASIAN CULT CINEMA (and its equally scrofulous same-named sister magazine) frequently listed a given actor under several different name spellings, sometimes even assuming the same person to be different actors! Other western writers and internet archivists, though, have been caught in similar traps, sometimes keying the transliteration to the actors country of origin, other times spelling it according to the credits of the film they're discussing, even other times trying to find the most common spelling among a variety of sources. This last method would be my method of choice were I to one day write a book on Hong Kong cinema, since enough material exists about it that some name spellings have become almost commonplace (at least to the English-speaking audience), but no matter what, it would still be diffiecult to please everyone. Nonetheless, I'm still fascinated by the fact that in the Chinese language, so many dialectic derivations can be taken from the same combination of three characters. I suppose the closest thing English speakers would have might be regional accents, but even then there doesn't seem to be the barrier to comprehension (in spite of a common "alphabet") that sometimes appears between Chinese dialects like Cantonese and Mandarin (and possibly others).
The best worst names have always been, and likely always will be, in the "adult" entertainment field, where you can find the likes of Candy Apples, Summer Daze, Holli Woods, Violet Blue, April Flowers, Amber Waves, Sindee Cox, Christy Canyon, Sahara Sands, Nikki Sin, E. Z. Rider, Jon Dough and Canada's infamous Peter North (think about that last one for a second).
In case you're wondering, I got all of these off the internet movie database as I have never, ever, EVER seen any of these people in action. Ever.
In some cases, it's just being pretentious on purpose. For instance, Chad Michael Murray has been credited a couple times as simply Chad Murray, so I don't think there's any SAG rule forcing him to use all 3 names. Just ego.