Wrap the input fields and other stuff into a <fieldset>
and give it the disabled="disabled"
attribute.
Example (http://jsfiddle.net/7qGHN/):
<form>
<fieldset disabled="disabled">
<input type="text" name="something" placeholder="enter some text" />
<select>
<option value="0" disabled="disabled" selected="selected">select somethihng</option>
<option value="1">woot</option>
<option value="2">is</option>
<option value="3">this</option>
</select>
</fieldset>
</form>