1. What blogging platform do you think is better, Blogspot or wWordpress? Maybe there are other platforms that I just know about it. To be honest, I prefer the comment structure of LiveJournal the best, but I don't think is as popular as other platforms.
People who use Wordpress will tell you it's the best. People who use blogspot/blogger will tell you it's the best. Personally I much prefer blogspot. But if you're the kind of person who likes tinkering behind the scenes, doing lots of add-ins and what have you, then by reputation, Wordpress will offer you more possibilities. I dislike that stuff and just want something simple that allows me to write so it's standard templates and blogspot for me. But then again, my blog is mostly for me and serves as my diary, except that unlike any paper diary I've ever tried to keep, I've been keeping a blog for nine years now (just noticed tomorrow will be my nine-year-anniversary - mad). Which leads me to ...
2. Do you think blogs that are more in the "journal" style have a chance to survive?
I always find this question amusing. Your blog will survive for as long as you keep writing it. There are just no guarantees that anyone will read it. So as 2Cent say, it's important you figure out what you want from your blog, is it readers or more for yourself as a public diary.
There is another thread here somewhere about blogs and how many hits you get in a day. You might find that interesting. For what it's worth, my blog, which is very much a diary for myself, gets between 50 and 100 hits per day. Mostly google searches but maybe between 10 and 20 regular readers, with up to about 10 of those regularly commenting. I don't monetise, try to optimise SEO or any of that stuff* and, without trying to put myself down, it's really pretty boring. But I love it regardless and it's a big help to me, not only in keeping a record of stuff but also in helping me to deal with things happening in my life. Even if that wasn't quite what I thought it would be when I started it.
*Shock, horror: I even often post without adding photos, something many "experts" will tell you is a big no-no. And when I do post photos, they're my own not usually very good ones, another big no-no - apparently I should be working on my photography skills until I'm good at it.