I got a similar problem here but the other way round -while i had the K-Lite codec pack installed (latest version) on my Vista Ultimate, everything would PLAY fine (avi, mpg, wmv etc) but when opening a folder that contained divx-encoded avi files, a "com surrogate" error would occur and sometimes explorer would crash.
I uninstalled the K-Lite pack and installed a "Vista Codec Pack" but i still had the same issues!
Kicked that one too and installed DivX latest version - STILL same issue!!
After some googling then i found that DivX itself is the culprit - regardless what version, it's just not really compatible with Vista. So i kicked that one too and installed the alternative Xvid - no more problems
However now i have a different problem - i used to do lots of video convertying but right now i am stuck due to a lack of codecs! Particular using a proggie called "SmartMovie" which converts pretty much any format into small avi files that are to be used on s60 smart phones, i always (under XP) had a lot of codecs to chose from, but right now it offers only Xvid (a version that's "built in") and ffdshow.
I hope that K-Lite will come with an update that is truly Vista-compatible soon... i need those codecs, every single one of them