OS bad...I think

[ecase]

Recently, my emachine laptop started slowing down and I got lots of "OS not installed", and blue screens. And of course, I cannot locate the original cd that came with it. I defragged, cleaned up disk, removed all tmp files and even restored to previous point. I get a more stable environment, but still extremely, extremely slow. How can I fix this? It happened 2 other times, and I took to Best Buy and paid them to fix. They reinstalled OS and it cost me $200! I have copied all my docs, pics thankfully. I am trying to not have to take it to someone again, cause money is not available this time.

Please help

 

[AWS]

Maybe your hard drive is going bad. Might want to make an image of the drive so you have it for when the drive dies completely.

 

[Antar]

Run any diagnostic software.
If u cann't download it, then set ur laptop HDD as slave to another PC.
but before don't forget to backup/clone entire drive.

As for software utilities:
for diagnostic have a look here
and this is free free backup/clone utility.