Hello,
Which browser is the main acting funny occurring in? I can't replicate in FireFox.
For the menu font size you can adjust here:
#s5_nav li a {
color: #ffffff;
font-size: 1em;
}
s5_flex_menu.css (line 138)
What do you mean spacing between lines, do you mean vertical? If so you can adjust the height here and this will decrease spacing:
#s5_menu_overlay #s5_nav li {
background: rgba(0, 0, 0, 0) none repeat scroll 0 0 !important;
border: medium none !important;
float: none;
font-size: 3.2em;
height: 83px;
}
template.css (line 2497)