Change the character encoding

Hi!

I tried to translate the name “comments” to “coment??rios” but the blog doesn’t show it.
On the other hand, the categories that I created using latim characters in the name work well.
Is there anything that can be done?
In the admin page there is a option called:

Admin > Options > Reading

where we can find an option called “Encoding for pages and feeds”. Do I need to change it? But what do I write in the place of “UTF-8” ?

Thank You!