no it has nothing to do with wether they are wired or wireless.
Both computers must be in the same group. so if you create a workgroup called home office both computers should be a member of it. You can do this through ICS which is use you main desktop to connect to the internet and use the laptop to connect to the other computer through its internet connection.
see this link on how to create a workgroup Create a workgroup - Share files and printers across your network - Weekend Project - CNET Reviews
Both computers must be in the same group. so if you create a workgroup called home office both computers should be a member of it. You can do this through ICS which is use you main desktop to connect to the internet and use the laptop to connect to the other computer through its internet connection.
see this link on how to create a workgroup Create a workgroup - Share files and printers across your network - Weekend Project - CNET Reviews