Hi, I'm Nathan.Sorry to hear that you're having trouble with this but I'll do my best to help you.
This type of problem is often caused by a contaminated laser lens. You can attempt to clean it by blowing out the disc tray/slot area with a can of compressed air for dusting computers (keep the can upright only so you don't get chemical propellant on the lens).
If this doesn't help, you can try a specialty cleaning disc (Allsop 23321 Ultra Pro Carbon-Edge DVD and CD-Drive Cleaner) which has little brushes that clean the lens more thoroughly.
If neither of these cleaning steps help, then this is more likely a hardware fault, which could include a bad laser emitter or pickup, faulty spindle motor or laser transport, bad d/a converter, etc. Any of these issues would require repair/replacement.
Let me know the results, and I'll advise further, if needed.
You're very welcome, Greg, and best of luck to you.
Thanks for the update, Greg.
I haven't set any further messages. The site (not me) sends out automated reminders to rate/close the question.
That isn't from me and I have no issues at all waiting for you to test this out at your convenience.
I do have to reply back here, as I have to make the last post or I won't be notified when you come back, just disregard the emails as they aren't from me and we can pick this up whenever you are ready.