MacBook Pro with Disk Utility code "Invalid Node Structure"

Hello, I need guidance please. Late last night I was listing something on eBay and my computer started to do the spinning ball a lot. It took 10 minutes to complete functions and then when my screen went dormant, I refresh it, it had the booting dial in the middle of the screen! I put in my Mac OS X Installation disk and it took long while but it booted. I then ran the disk repair and there were a lot of errors... one error was about the directory , lots of missing items that it said to look at the "Missing and Found Directory" that the numbering was off and "Invalid Node Structure". At the end it wanted me to back up my files and erase the hard drive. I don't have an external drive. I was reading about Disk Warrior and was wondering if this will save the computer or is my hard drive going to die anyway? I purchased Cardonite last night and was hoping to save my computer so I could back up all the files. But I didn't know it would take several days until I got the email explaining that. Can someone help me?

The very first thing to do is backup that drive! Do not use Carbonite as that could take days and your drive may die during that time. Use an external hard drive and backup software such as Carbon Copy Cloner or SuperDuper. You also have Time Machine built in which you can use.

The errors you received are probably going to mean you have to replace the drive with a new one. I wouldn't spend $99 on Disk Warrior.