You can change in layout file (`customer.xml`) at location `app/design/frontend/<your_package>/<your_theme>/layout/customer.xml`


    <default>
            <!-- Mage_Customer -->
            <reference name="top.links">
                <action method="addLink" translate="label title" module="customer"><label>My Account</label><url helper="customer/getAccountUrl"/><title>My Account</title><prepare/><urlParams/><position>10</position></action>
                <action method="addLink" translate="label title before_text" module="customer"><label>'Reg'ister</label><url helper="customer/getRegisterUrl" /><title>Register</title><prepare/><urlParams/><position>100</position><li/><a/></action>
            </reference>
           
        </default>