[Hampshire] Saving an old DVD drive

I have just rescued an old Win 98 PC from the skip and brought it back
to life by installing Ubuntu.
There is just one snag. The DVD drive worked for the installation and
works playing audio CDs but when I tried playing a DVD with the movie
player, the intro played but then I got an error presumably when the
main video should start.
I tried again with VLC but got an "error reading block 0 "
dmesg gives "__ratelimit: 37 callbacks suppressed" followed by a 10
lines of "Buffer I/O error on device sr0, logical block 177xx"

I can browse the DVD and see the file names and sizes but I cannot copy
a file off it dmesg giving a lot of "end_request I/O errors" and
"attempt to access beyond end of device"

Is there anything I could tweak to get it working?

Thanks

Roger