|The second image seems to show that you are getting a message from a Linux OS, not the mboard's bios.|
I'm assuming you don't have a bootable disk with an OS on it inserted in a drive or a USB port that should not be there for a normal boot that may be interfering - if you do, eject it, or unplug it, then try booting.
If you were dual booting Linux and Vista, assuming you have at least 2 hard drives that have the operating systems on each of them, the physical hard drive for whichever operating you installed last, which presumably determines whether you get a screen where you can boot either OS on if you used the multiboot feature built into the OS, has to boot first in the bios Setup settings.
Why would that change?
When you disconnect a drive, then boot the computer without it connected, then connect it again, the boot order settings may have changed so you're no longer booting from the proper physical harddrive.
The same can happen if you change where or how the physical drives are connected.
If you have at least 2 hard drives that have the operating systems on each of them, go into the mboard's bios Setup, and make sure the drive that you booted from first previously boots first now.
You can either -
- find the list of hard drives near the boot order list or similar that lists which hard drives you have installed - usually they are listed by their model - the one you want the computer to boot from must be listed first (on the top).
- or - less likely - there may be no separate list of hard drives - but you can select individual harddrives to boot from in the boot order list or similar - the one you want the computer to boot from must be listed first (on the top).
I'm assuming you were not using a third party boot manager program to be able to boot two or more OSs. If you were, you need to consult the help info about that program in order to fix your problem. E.g. I used BootIt! New Generation on a friend's computer - if it isn't booting from the right partition, if you boot from the configuration floppy or CD, the booting problem is detected and it prompts you to allow it to fix the problem.
NOTE that, if you have at least 2 hard drives that have the operating systems on each of them, the proper hard drive must be booted from in that case too !
Why would which partition you boot from on a multiple partition hard drive change?
If you boot with an operating system CD, the partition booted from may change to that for that OS, rather than it booting from the partition for the third party boot manager program.
E.g. that happens when I boot with an XP CD on my friend's computer that has BootIt! NG and is dual booting XP MCE 2005 / Vista Premium. I insert the configuration floppy for BootIt! NG, it finds the problem, it fixes it if I let it.