Most of the OS-specific properties are not readily accessible by a program (or, at least, not by any standard all-in-one tool), but can be accessed by reading files in the /proc and /sys directory structures. For example, by reading /proc/cpu, you get a pretty exhaustive list of the CPU features on your system, while /proc/version gives you the detailed version of the Linux kernel, usually including the time it was compiled, the user who compiled it, and what compiler was used to compile it.
You also can try lshw - a tool that will scan the system and list out all hardware devices based on the diagnostic responses the equipment is designed to output.