I have just got the Optio S5Z and cannot playback the video clips on anything but Windows Media Player. (Downloading them is fine)

My Adobe Premiere won't import and Pinnacle Studio say it doesn't support MPEG4???

I use professional cameras in my work (hence Premiere) and use the Pentax for rough and ready 'extra' bits. I know nothing about the different MPEG codecs, so my question is:-

How can I convert these files (import to Premiere or at least Pinnacle 9) without having to burn to DVD and then re-rip them back again?

Thanx