Does Win 7 work inside vbox with os/2 host?
1. Win 7 works in VBox 5.0.6 for OS/2 and can be installed within a VM of VBox 5.0.6 for OS/2.
Shared sound does not work, shared clipboard does not work.
Networking DOES work for Win 7 guests. Make sure you choose the "Intel NIC for servers" as the network adapter reflected into the VM. It is a known issue that not all other NICs work.
2.) Win 7 can be made to work inside VBox 1.6 for OS/2. You have to create an appropriate .vdi image on VBox for Win and use that in Vbox 1.6 for OS/2. You have to use older guest additions (those for Vbox 2.1.2), not the latest ones. Shared sound does not work, shared clipboard does not work.
Networking works for Win 7 guests using the AMD C579 NIC and driver (not included in Win 7!). The Intel NICs do not work.
In general stability of the whole machine is better with 5.0.6 and the guest runs a lot faster in 5.0.6.