Ok then, if you have a CD Drive and you know it works then:
1. On the bck of the CD Drive are two leads leading off - a wide thin one - the Data Ribbion and one with four leads (Red Black Black and Yellow) which has a chip off a corner to show which way round it goes. Take these two out and make sure you put them somewhere they won't gt lost - don't pull them out at the other end!
Remember the Dirction of the Ribbon Cable for when you put it back on
2. The CD drive is attached to the Case by Two Screws (on either side if the case opens like that), undo these screws. Make sure the CD Drive is held up so it doesn't fall and snag something.
3. Take the CD Drive out
4. Put the new CD drive in - and put all the cables in as you found them. the power will not go in the wrong way round but the Ribbon may - don't forget to remember the way it came out!
5. Put the case back on and power it up. When it boots up and you get onto Windows - put a CD in which you know works, wait a little while for t to stop spinning, and then check it.
I'll be interested to hear how it goes. To save time it would help if you knew the CD Drive works first.
A Knight is sworn to Honour. His heart knows only Virtue. His blade defends the helpless. His might upholds the Weak. His word speaks only truth. His wrath undoes the Wicked.