This is a very common problem in various computers .
The copying speed is reduced to around 1.0 mb/second.That is the cd drive copies at approximately 6x speed.The read speed is considerably reduced.This normally happens because after retundant cyclic errors the drive considerably reduces the read speed.The only easy way to increase the drive speed back to normal (say 48x) is to uninstall the IDE controllers and then let windows cofigure and reinstall it during the next startup.
To uninstall the IDE controllers, right-click My computer (In windows)and select properties.Click the Hardware tab and then click Device Manager.In the Device Manager expand the IDE ATA/ATAPI and then Right-click the ATI IDE Controller and then click uninstall.
After uninstallation the CD-drive icon will disappear,but do not worry . Just restart your system and windows will do the rest of the process of installing the driver back and you will get the CD-drive icon back.