Few questions about picture icon on comments

I see that the pictures on comments are 45 x 45, where can i change it to different size?

and does this work?

when users upload the picture, its create a small picture with that dimension? (45x45) ?

open /templates/base/css/cmts.css
match these two clases up with below

.cmt-head
{
position:relative;
border-top:1px solid #CCC;
background-color:#EEE;
padding:2px 2px 2px 26px;
font-size:11px;               
line-height:33px;
}


.cmt-icon
{
position:absolute;
left:3px;
top:3px;
width:30px;
height:30px;
border:1px solid #CCC;
}

Thank you..

But What create this picture, so small?