I just saw blogspot is providing few good templates by default for their users and as they are cool i thought to change one of my blog template. We can customize its background, header, layout and most of the things but what i want to know is putting default template in your blog is good for SEO? I mean most of the third party template we are using in our blog have broken code and is not good at all for our blogs SEO. So is it good to put default templates as i think they are SEO optimized? Correct me if i'm wrong?
Yes, your theme needs to be coded correctly or it will cause you problems. A properly coded theme, for the most part, is not any kind of big determiner to how well you will do with SEO. You can achieve good SEO with just about any theme that is coded properly. It doesn't have to be a certain type of theme. You can take an "SEO friendly theme" and still not rank well. It's not the theme...it's the performance and knowledge of the person doing the SEO. If you are getting poorly coded themes, I suggest that you stop using free themes...that is the risk with using them. At the least use a well known, reputable source.
I am thinking to move from blogspot to self-hosted WordPress blog. Hope it will be a solution for every SEO question?
Yes, I think wordpress is great for SEO, but, you can perform good SEO on any website, on any platform. It all depends on how well you know what you are doing.