Archie,
You can only change the size, face, weight, and colour in HTML email only. I believe you can use a CSS style sheet in your email, ie:
<html>
<head>
<style type="text/css" rel=stylesheet><!--
body { font: 9pt verdana; color: navy; }
.custom { font: 10pt verdana; color: blue; }
--></style>
</head>
<body>
Welcome to another issue of <span class=custom>My Newsletter</span>!<br>
<br>
...
</body>
</html>
For a CSS stylesheet to be loaded by HotMail I believe the <style> tag has to appear AFTER the <body> tag.
You can also use CSS inline:
<span style="font: 9pt verdana; color: navy;">Welcome to another issue of <span style="font: 10pt verdana; color: blue;">My Newsletter</span>!<br>
<br></span>
Or simply use basic HTML:
<font size=2>Welcome to another issue of <font size=3>My Newsletter</font>!<br>
<br></font>
Regards