It's quite easy since you have tons of choices to do so. My suggestion is simple but effective. You can dowload an add-in program called PPT2Flash which allows you to convert FLV to video within steps.
You can dowload if here
I'm a videographer and a web developer and from what I know about video, I would urge you NOT to do this. PP is a slide show and slide show videos are not as effective at getting your message across as is a dynamic video that properly incorporates motion and audio.
Instead, start over, using your PP as an outline for your video production. You could hire a local wedding videographer at a very reasonable rate and have the benefit of his professional equipment and know-how.