You can do that. Insert the below HTML/PHP code snippet where you would like to have the login forms.
<form action="http://domain/MyBBforums/member.php" method="post">
<table border="0" cellspacing="1" cellpadding="4" class="tborder">
<tr>
<td class="thead" colspan="2"><strong>Login</strong></td>
</tr>
<tr>
<td class="trow1"><strong>Username:</strong></td>
<td class="trow1"><input type="text" class="textbox" name="username" size="25" maxlength="30" style="width: 200px;" /></td>
</tr>
<tr>
<td class="trow2"><strong>Password:</strong><br /><span class="smalltext">Please note that passwords are case sensitive.</span></td>
<td class="trow2"><input type="password" class="textbox" name="password" size="25" style="width: 200px;" /></td>
</tr>
</table>
<br />
<div align="center"><input type="submit" class="button" name="submit" value="Login" /></div>
<input type="hidden" name="action" value="do_login" />
<?php
$domain=$_SERVER['HTTP_HOST'];$relativePath=$_SERVER["PHP_SELF"];
$curpurl=$domain$relativePath;
?>
<input type="hidden" name="url" value="<?php echo $curpurl; ?>" />
</form>