Hi Ed,
Actually that's pretty easy to do.
Create your first snippet like so, assigning the tab trigger to whatever phrase you like:
<select> <option value="$1">$2</option> opt$0 </select>
Then create a second snippet like this:
<option value="$1">$2</option> opt$0
I have assigned this snippet to a tab trigger of opt. If you call yours something different, you need to change the opt reference in the two snippets. When you use the first snippet, you'll tab through the two values, then tab to the end of "opt", press tab again, which triggers the opt tab trigger. The same will happen in the second snippet. The only caveat to this is that when you've added all your options, you'll have to manually delete out the last opt tab trigger word. I don't think there's any way around this but is not a major issue. I'll happily be told if there's a better way!
Hope that helps.
Andy