LinuxQuestions.org - errno 5) input/output error

after I put dvd in,it load to the screen.I click on accessories, terminal. ubuntu@ubuntucame up.I typeing instuctor.But it keep saying no such files or directory.
Try it other way, it say only root can do that .

So I click on the install icon,fill all field.instlation
system copying files up 32 percent then it fail as befor.

The install encountered on error copying files to hard disk. ERRNO 5) input/output error.
this particular error is aften due to faulty cd-dvddisk or drive or faulty hard disk, it may help to clean the cd/dvd to burn the cd/dvd at a lower speed. or clean lens.
To check whether the hard disk is old and need of replacemint.

I buy the dvd fromweb site, cd-rom is fine, I clean the dvd the lens. The hard disk is 7 years old was running winwows me, Iclick on somthing that give this error report. lot of foldercame up. Target show 3 of those folder. CD-ROM, INITRD.IMG.VMLINUZ. Showan arrow from on the top of the folder point up.

BY the way when i install ubuntu. I use the entertir drive. Do you think my hard disk is shot?

I never realize lenex givso much problem until I reed sum of those Q and A.

Any help would be welcome.
C J.