Patent ID: 7337313

Claim:
A computer comprising: a processor; an input device; a storage medium storing a basic input/output system (BIOS); a hard disk drive (HDD) comprising a hard disk, the hard disk comprising a first partition, a second partition, and a boot block storage section, the first partition storing an operating system (OS) to be executed by the processor, the second partition storing data for use in restoring the OS to a predetermined state for system recovery, and storing restoration software to execute processing to restore the OS to the predetermined state for system recovery by using the data, and the boot block storage section storing a boot block having partition information indicating which one of the first partition and the second partition is an active partition; and a storage section storing an active-partition switching program to be activated by the BIOS upon depressing a specific key of the input device and to change the partition information of the boot block so that the second partition becomes an active partition and the first partition becomes an inactive partition, the BIOS causing the boot block to activate one of the OS stored in the first partition and the restoration software stored in the second partition, based on the partition information.