Are blogs and blogging safe?

Yes.
Yes, if you share your thoughts, ideas, poems, pictures and just generally have fun.
To begin blogging, you firstly need to create a safe site that may not harm yourself or your audience. To build a site easily, you can build a WordPress site, for there are many free and premium themes, say in http://www.mageewp.com/, you can find kinds of themes to build your site.
You could potentially open yourself to stalkers and pedophiles who actually go looking at blogs for easy targets. There have been numerous cases where some perv' found his victim through their BLOG because of an address or other identifying information.
Here's some rules and notes to keep in mind when using your blog.
Never post your phone number or home address. Avoid posting your School's name or adderss/location, especially if its a small town. Photos of you which "give away" your location, like standing on your porch with the addess and street sign visible.
Be careful about how descriptive you are with the place you live. I can say, "I live in Washington and really enjoy the beautiful countryside" and that's fine. But if I were to say, "I live in Washington and really like to hang out at the Red Apple store behind my high school on my way home to my pink and yellow striped house with no doorlocks..." all a clever stalker would have to do is Google for all red apple stores in Washington then mapquest them to see which has a high school near it. And easy drive to that location, looking for pink and yellow striped houses and I am good as dead or worse!
have fun be careful. there's weirdos and hateful people out there amongst the good people.