Firstly, there is no such thing as Windows Vista 7.
Secondly, that message will be coming from the BIOS, because the disk is unbootable, in which case it will not be possible to get into Safe Mode, or into any of the repair tools on the disk.
One of the following will be the case:
1. The computer is configured to boot from other devices (such as DVD or floppy) and there is a non-bootable disk in the device.
2. There is a hardware fault with the disk itself.
3 The bootloader or MBR has been corrupted
4. The BIOS is corrupted.
The first thing to check is that the DVD drive, etc. are empty.
If not, remove any other disks and reboot.
IF that doesn't solve the problem, then you need to to is get into the BIOS and check that it is recognising the hard disk, and (if it is) that it is configured to boot from it.
If the hard disk is not recognised in the BIOS, then the chances are the disk or its controller have failed.
If the disk IS recognised then it could still be a failed hard disk, but it might also be that the bootloader or MBR has been corrupted.
If that is the case, then you will need to boot from a Windows disk (or USB stick) or the recovery partition (if there is one) in order to repair it.