discovery - Which way should I display time zone names to make them easily pickable?

We have to present a list of time zones to the user from which they select the one that applies to them.

We have a choice about how we display this information - either:

Time zone name (Offset)

or:

(offset) Time zone name

Windows uses the latter approach, but I'm not sure.

How do people pick their time zone? Do they look for the name (Central European Time, Pacific Time, etc.) or do they use the offset from GMT or UTC?

This leads onto a supplementary question - should the offset be displayed relative to GMT or UTC? Windows XP used GMT whereas Windows 7 is using UTC - or at least that's the case for the machine I'm using.

Answer

In the few times I've done this, we've always followed the format: Time Zone Name (offset)

In very brief user testing, we found that users looked primarily for their time zone name and didn't always know the offset from GMT (or UTC). So we have that field first. I don't believe our users knew (or cared) about whether the offset should be from GMT or UTC.

This was for a form available to a broad public audience in the US. Our findings might not be the same if your audience is more technical or outside the US.