buy an internal burner of your choice + an enclosure, screw it in & it's done.
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&Description=dvd%20encl osure&bop=And&Order=RATING
i have the macally, it's good and presentable. if your moms machine doesnt have usb2 it should still work, but slower. theres a firewire version too but costs more.
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now if you want dirt cheap maybe this might work for you, it's not like you're getting some kind of mission-critical product
http://www.newegg.com/Product/Produc...82E16827106278