I start up my computer, but befor e I can get on a site the thing stops working...whatever I click on makes no difference. I have to hold in the start button for 5 secs to switch off, then start all over again. I have just been playing cards (NOT connected to the internet) and it STILL froze after about 5 mins. (It DOES work about 50% of the time) Is there anything I can do about it please???