Sony Viao issues

Question

I am thinking about buying this sony viao from a lady for $200, she told me what was going on with it and she said '' It starts up and when windows starts to load it blue screens and shuts down. It will do this continually until you manually shut it down.'' What might be the problem and is it worth buying and fixing. I'm not lookin to put in 300-400 dollars into it. I can handle 50-100 dollars. Someone told me its probably the hard drive needing replacing, then i was told it was a great deal and once i get it home do a constructive recovery on it..
Being tech's..what do you think the problem may be and is it worth buying and fixing? Thank you so much