If you do not have the passwords for your system, there are ways to reset the root password. I'm not sure what Linpus shows when it is booting up, but, if you see the grub screen (it would be the screen that has a list of kernel, and maybe a choice for memtest) you can stop the boot at that point and add a "1" to the kernel line and then go through a few commands to reset the password. We need to know if you see the grub screen first. Maybe give a list of what screens or what screen changes you see while you are booting up.
I'm looking into what the Linpus system looks like, I mentioned it in another thread that you wrote. If I can find something, it'll make it easier to help you. If you can tell us what you see, it'll make things easier.