hi, wondering if anyone can help, for the last week or so everytime ive turned my e system 4213 laptop on, its making a noise from the disc drawer as if its trying to eject a cd, when i have gone to use nero yesterday, it started burning then 20 secs in, it said there was a calibration error,tried lens cleaner,no joy, i then tried again to put a cd in to burn and it kept saying please insert a disc, when they was a disc in!!!! it is not making the whirring noise or anything now when i put in a disc, its not coming up on the screen that i have a disc in or anything but when ive tried to use nero this morning , its still not finding a disc but its now saying unknown burn phrase???? please help as this has got me demented thankyou

If i was to buy a new one how hard would it be to fit ? thankyou