What linux distribution the box is using:
cat /etc/issue

What kernel version the box is running:
uname -a

Sample Output:

kenglish@bowls:~$ uname -a
Linux bowls 2.6.20-16-generic #2 SMP Thu Jun 7 20:19:32 UTC 2007 i686 GNU/Linux
kenglish@bowls:~$ cat /etc/issue
Ubuntu 7.04 \n \l