Yes, yes, and yes. But without seeing the site and exactly what you are talking about, hard to say anything more specific.
thanks WPyogi – but just empty default site right now – nothing to look at yet…
I did load twenty twelve theme and that is a good start
In general, layout and appearance are controlled by the CSS code — so spacing can be changed using CSS modifications. But sometimes, extra space is created by other things — HTML coding, or code errors, so it’s a bit hard to say unless there is something specific. One thing for sure, though, is that if you want to make any changes to a theme, you’ll want to use a Child Theme or a custom CSS plug-in — so that your changes are not erased when WP or the theme is updated.
And in the case you posted about initially, the space may have been due to the site having no content yet — the space was “reserved” for content but looked empty because nothing was there yet. So definitely put some content (even “dummy” content) in your site before worrying much about how it looks!
I see above that you installed twenty twelve. If you use the twenty twelve theme instead you can fix the issue. Twenty twelve, the new featured theme, allows you to choose whether to use a text title or not. You can also upload a very narrow header instead of a huge wide one. Of course the title text is still there in settings for the search engines. I used my logo, which has the site name and created a narrow header that explains what the site’s about. good luck, Kristi
