4.20 The Host Keys panel
The Host Keys panel allows you to configure options related to SSH-2 host key management.
Host keys are used to prove the server's identity, and assure you that the server is not being spoofed (either by a man-in-the-middle attack or by completely replacing it on the network). See section 2.2 for a basic introduction to host keys.
This entire panel is only relevant to SSH protocol version 2; none of these settings affect SSH-1 at all.