The headset has nothing to do with languages or accents - that's done by the phone itself.
As far as headsets, that's really a personal matter - there are many good ones out there. I've always preferred Jabra and Motorola headsets, and currently use a Motorola H720. Even though I'm hard of hearing, I can hear pretty well with it.
If you prefer one that sticks into your ear, the Jabra Wave is also pretty good. (I'd have to take my hearing aid out every time I'd use it, which is why I changed to the H720.)