how to adjust template

I want to adjust some details in my template, how would i do?

1.I need logo overspread this area. But now, there have two bars that black top-margin and bottom-margin. How to remove these margins.

2. The distance between top-menu options is too short. I need adjust it.

Which code should be changed in css??

Use FireFox firebug plugin; or you can use the one built into Chrome but firebug is better.  Turn off CSS caching in Dolphin, clear the caches.  Now you can use Firebug to see what class or ID is controlling what.