If you do decide to remove the navbar insert following code in your CSS part of template

The Navbar is the slim colored strip about 30 pixels in height..........

running across the top of your webpage/blog. You are given an option in the Page Elements subtab under the Template tab to change its color but not to remove it.

LEGAL ISSUES

The Terms of Service for Blogger can be found here. Iagree with Digital Inspiration what he say here about the legality of removing the navbar and I quote :

"The Terms of Service for Blogspot.com do not mention anything about Blogger Navbar but it does state a word about the discontinued Blogger AdBar which was previously displayed on freely-hosted Blog*Spot blogs.

By creating your BlogSpot Site, you agree that Pyra has the right to run such advertisements and promotions. You also agree that you will not attempt to block or otherwise interfere with advertisements displayed on your BlogSpot site via JavaScript or any other means. Doing so is grounds for immediate termination of service. The manner, mode and extent of advertising by Pyra on your BlogSpot Site is subject to change.

Since it is not mentioned explicitly in the Terms of service, it remains doubtful if removing and hacking the Blogger navbar is any violation of the Blogger terms of service. Lets say we are not "removing the navbar" but only "hiding the navbar" or we could even re-position the navbar to the bottom of the blog. Get rid of the blogger nav bar."

If you do decide to remove the navbar insert following code in your CSS part of template :

#navbar-iframe {
height:0px;
visibility:hidden;
display:none
}

before this line :

]]></b:skin>

To know what is CSS part of template


After removing the navbar there may be a blank strip on top of your page. To get rid of it add this in CSS part of your template :

body
{
margin-top:0px;
}

If this doesn't remove the gap created with Blogger Navbar, try the following CSS hack

body
{
margin-top:0px;
position: relative;
top: -50px;
}