You could leave until completion if only to try and recover some data, but expect some data loss.
An alternative could be to do a power shutdown but that could cause more problems.
I think you're just going to have to patient as it is at least progressing.
The SeaTools disk will probably just confirm HDD damage without effecting any repairs.
Ultimately I think you're going to have to take this in to a reputable tech who should be able to recover some data by booting up with a Linux disk, replace the HDD and reinstall your OS, but it will be indeterminate as to what data will be lost.
Programs can be reinstalled but personal stuff may be gone forever.
