WD8001032 external don't work right

I have a WD8001032 model external hd that i’ve had since 2005 and when i plug it into any pc it won’t work right. When i try to click on folders, it takes a long time then eventually gives a “not responding” error. Not sure if its bad sectors or what but i am able to right click c/p some things to laptop desktop but even that eventually stalls and i dont get all the files. It’s  80GB and 90% full. Not sure if thas an issueor not. Hopefully theres an inexpensive solution to this isssue and someone can help. Thanx