col2-right-layout is mentioned in
app/design/frontend/base/default/template/page/2columns-right.phtml
or in Magento 1.3
app/design/frontend/default/default/template/page/2columns-right.phtml
If you want to swap the layout I'd suggest changing it in one of the layout xml files. For the shopping cart edit app/design/frontend/base/default/layout/checkout.xml
change
<checkout_cart_index translate="label">
<label>Shopping Cart</label>
<remove name="right"/>
<remove name="left"/>
<!-- Mage_Checkout -->
<reference name="root">
<action method="setTemplate"><template>page/1column.phtml</template></action>
</reference>
to
<checkout_cart_index translate="label">
<label>Shopping Cart</label>
<remove name="right"/>
<remove name="left"/>
<!-- Mage_Checkout -->
<reference name="root">
<action method="setTemplate"><template>page/2columns-left.phtml</template></action>
</reference>
And similarly for the checkout page in the same file change
<checkout_onepage_index translate="label">
<label>One Page Checkout</label>
<!-- Mage_Checkout -->
<remove name="left"/>
<reference name="root">
<action method="setTemplate"><template>page/2columns-right.phtml</template></action>
</reference>
to
<checkout_onepage_index translate="label">
<label>One Page Checkout</label>
<!-- Mage_Checkout -->
<remove name="left"/>
<reference name="root">
<action method="setTemplate"><template>page/2columns-left.phtml</template></action>
</reference>
As always it is better to make a copy of the file you are editing to your own theme.