Print Screen function does'nt work any more

When i try to do a screenshot of the desktop or the application (using Alt + Print Screen or Print Screen) i can do the screen capture but when it comes to pasting the screen capture into a document or into anythink it just either freezes the computer and you have to do Ctrl + Alt + Del and End Task the program you are trying to paste it into, or sometimes it even crashes the PC and i have to hit the Restart button on the front.

Has anyone had this problem?

Does anyone have an idea as to stop and irradicate this problem?

I do know quite a lot about computers but not that much as to fix this problem.

Thanks
Paul

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My PC spec is below:
AMD Athlon 1.4Ghz
MSI K7T266 Pro Motherboard (MS-6380)
512Mb DDR RAM
60Gb & 80Gb HDD's
GeForce2 MX400
Windows 98 SE

 

Printscreen copies the contents of desktop to RAM.
If RAM is full/overused, the contents get moved to the swap file.
If swap is corrupt, or not big enough...problems.
If RAM is overused (to the point where the swap is ALWAYS in use), everything can grind to a halt.
Have you manually resized the swap?
Have you got a ton of programs running, and RAM is used?
When was the last defrag?