DO NOT BUY A REFURBED ONE!!!!!!!! What is her budget on what she wants to spend? Celeron chips are second rate go for a genuine dual core intel or AMD equivalent. Make sure it has a minimum of 2 GB of RAM otherwise it will be slower than cancer. I'd recommend spending between £400-500 that way your going to get something that is going to last and still run well. PC world are good to buy from as they offer a deal whereby if you pay £7.95 a month any problem hardware or software they will fix it for free. That way if you don't have someone who is tech savvy she will always get it sorted if she gets infested with spyware or a virus. In order of greatness the best laptops are Toshiba, Sony, Asus, HP, Acer, Dell. What ever you do DO NOT BUY A COMPAQ. I wouldn't piss on one if it was on fire they are awful machines.
Hope this helps m8 any probs send me a pm.