Changing vertical alignment of teasers to horizontal
I think you'll have to investigate a bit further into your site structure generally. ;)

Assuming that you have content types of articles and basic pages on your frontpage, you could try something like this in your CSS:

.node-promoted {
float: left;
margin-right: 20px;
max-width: 280px;


}

"node-promoted" is the class one of several classes of teasers of articles and/or basic pages promoted to frontpage. You can use the almighty Firebug-Addon for FF to find this out ...