What's the best Codec pack out there?

I just wiped my HDD clean to factory settings, now I need real good codec pack. The last codec pack I remember installing was, I think, was the K-Lite codec pack. Any suggestions?

er, I haven't installed any codecs specifically but I did install Win XP Service Pack 2 and Nero ShowTime (which came with the DVD burning program bundle). Would it be safe to just install the codecs?