Lesson for the Day BACK UP Files

Well I could cry, I was working my family research on http://www.ancestry.com/ last night. My plan for this last week and now starting on 2nd week is to work on my great grandfather Arthur Hall family. I had put in his brothers and sisters names into http://www.ancestry.com/ to see if I could find any information.
On my to do list I want to see if I have them in my family tree program. This morning I open up my family tree file. Nothing is left in my program except about 20 names. Some how when I was working on a part of my family I saved this information over my family tree program.
How did I do this I do not know but everything is gone. Over 10,000 names.
We pull out my family tree back up file and my CD drive is not working. Will not read the file. Hubby puts CD in to his CD drive. He can see that I have information on the CD but he does not have family tree down loaded on his computer so of course can not open.
What do I do? Take computer to Best Buy to see own much to fix my CD drive on a computer that is 4 years old? I know that I can not buy a new computer. I guess my plan is to see how much a CD player that I can plug into my computer cost. That is my first plan and then i will compare to getting my computer fixed. In the mean time I am sitting here very sad and wanting to cry.
So lesson is back up your files. I know I did not back up all the information I had on my family tree program, but there is a lot there.