Which one is best depends on your needs. Here are some considerations to make when choosing which is best for you:
- do you want to install it yourself?
- or do you want it to be hosted by a company?
- do you want to be able to modify the software? (If so, choose a open source platform)
- do you want a free platform?
- or do you want to pay?
- What features will you need?
- How do you intend to use it?
- Do you need it to tie into any existing software you use?
Given all of that
- LiveJournal is best if you need control over many things
- Blogger is the easiest if you just want to get going