Somebody use meta description and keyword tags for blogger blogspot? Or is better, that you don't use it. Because blogger put same meta description and keyword tags every page and this don't like the Search Engines.

I do use those meta tags on my blog in blogger. still find it useful even if its ignored by some SEs.

I haven't done it yet because I'm lazy but it seems other people have/are doing it in Blogger. Here's a blog that explains how to do it in Blogger. Read the comments before you do it so you can get answers to possible questions you may have before you have them.

blogger-tricks.blogspot.com/2007/05/meta-tags-for-blogger.html

I have used only description in my blogspot. It will be useful or not?

It will probably be useful. I've noticed that a friend of mine is indexed for phrase that I covet and the only place she uses it is in her description.