Yes, the space occupied by an element is
margin-top
--- size of the actual element
top-border width
padding-top
height
padding-bottom
border-bottom
-- // size of the actual element
margin-bottom
And iirc margin can't always be determined just by looking at one single element, since it can be preceeded or followed by a negative margin.
But I believe you could also alter the encasing element
ul.menu li {
vertical-align: center;
}