Every system connected to a network should have a unique name.
Replace mepis1 with whatever name you wish to call your system so it can be identified by Windows machines. HINT for dual-booters, we recommend using the same name that you Windows system uses to avoid confusion.
If you are not connected to a Primary Domain Controller, you can leave the example.dom as it is.
If your Windows machine has XP Home and you have never changed the workgroup name, then it will most likely be MSHOME, for XP Pro and later version of Windows, it is normally WORKGROUP. If you have no other machines on your network, you can leave mepisgrp as it is, otherwise, change mepisgrp to whatever you wish to use.