Which is better? Blogger or Wordpress? That depends on your needs and wants. But a free Blogger is hands down better then a Free Wordpress. Blogger is most generous with giving users unlimited space and bandwidth. Plus you get 100% total control of your blog to configure it anyone you want.
Wordpress is a lot more stingy with their offering for a free Wordpress blog. For starters, you only get 3 gigs of space on a free account, and very limited features and authority to configure your blog. They want you to pay for full control.
IMHO Blogger is a better more robust system then Wordpress. I’ve been saying that for the past 15 years! A hosted Wordpress while free, is totally configurable but your responsible for your own bandwidth and space. Hosted Wordpress blogs are also easier to hack in to and always have been. Your better off to just get a paid Wordpress account and purchase your own domain name for it. Better protection on Wordpress server then most servers out there unless you want to pay for a heavily secured dedicated server.
If your running a business, you will probably opt to using Wordpress. Understandably beneficial for Businesses that need total control and money is no object!
Most people will be better off with a Blogger blog. If you’re a business, you may want to use Wordpress but honestly I see no real advantage. Because whatever you can do on Wordpress, you can do on Blogger including getting your own domain name too.
There is no SEO advantage over one or the other, it boils down to looks and personal preference. Which ever way you go, back up your blog! Many people use BOTH! I even use both! I wish Wordpress was not so stingy in there free hosted offering.