First of all are you using a router or is your computer directly connected to the internet? If you are not using the router then you must change the network type of the virtual machine.
http://handsonerp.com/oracle-financials-tutorials/76-03-oracle-e-business-suite-installation-inst/6334-configuring-virtual-machine-network.html

If this does not apply to you then:

1- Find out the ip address of your linux machine by issuing ifconfig command.
2- Ping the linux machine from Windows by using ping command.
Please post the results of the above two.
The output will dicdate if the problem is in the network of the settings elsewhere.
Thanks