bedlam - 10:11 pm on Feb 8, 2010 (gmt 0)
I hate to tell you this after all the work you put in CyBerAliEn, but that looks like an ordinary serialized [php.net] array to me (though as-is, it can't be unserialized...probably what's pasted in the first post is not precisely what's returned by the query...)
This means you can get the un-serialized array back by running the query result through php's unserialize() function [php.net]. After that, it'll be possible to just access the data in the array normally.
Based on a very quick look, it looks like you'll need to find the key of the item in the 'votes' array with the largest value and return the value corresponding to the same key in the 'choice' array.