Well, it depends on the errors your hard drive has. If the hard drive has serious mechanical errors then you should replace it as soon as possible because it's just a matter of time before total failure and you'll lose all your data. A backup is recommended in case it's still possible. I would like to recommend a software which shows the health of your hard-drive. It's called HDTune and it's available for downloading from our website. You don't need to install it, just double click the package and go to
Health Tab and see if there are any errors. Errors and warnings will be marked with red and yellow color.