Slideshows are a perfect way to show off your products. There are a number of options for creating video slideshows that you can then upload to youtube and use to promote your shop.
1. Make sure you add your website/shop url to the video description so people can click it. It should also be in the credits of your video.
2. Get good music. Some services offer music you can add and Podsafe Audio is also a great resource for music (most is under creative common licenses, with artist attribution required). Make sure any music you use is available for use in videos or you risk having your video pulled by YouTube.
3. Give your video good tags, for example etsy, handmade, jewelry/soap/clothing/etc. and put it in the appropriate category (How To & Style works for most handmade stuff)
4. Get the word out. Embed the video on your blog, add it to facebook and other social networks, add it to a Squidoo lens, etc.
Online Slideshow Makers
I'm only linking to online slideshow makers since they should work on any operating system. There are a number available online for download and you can also use most video editing software to make them too.