A blog is a blog where content gets updated on a regular basis. It displays in reverse chronological order. To avoid confusion with server log, weblog was named blog. A blog is in fact one page with monthly archiving. It needs to be updated with new content periodically; otherwise, people will lose interest in it. http://en.wikipedia.org/wiki/Blog
One of the advantages of the blog is that you can speak out whatever is in your minds. You get what i mean.
Whereas, a website is a collection of web pages. The first page of a website is called home page. A website has a defined domain name (address) on the world wide web. Websites basically aren't updated as often as blogs, they stand more for longer lasting information - certainly depending on their actual purpose. http://en.wikipedia.org/wiki/Website
Now one of the advantages of having a website is that it is really yours. You are in control of it. Meaning, you decide on what to do with it and how to make use of it. One of the disadvantages is... it comes with a price. But price doesn't really matter if your need to see some real results on your profits.
Though the two often contradicts each other, it is a good idea that you get the best out of the these two worlds. Get yourself a website that will carry your, let's say, online catalog. And create a blog that will complement your website. Is that simple.