You can run your Mendix application by the Mendix Modeler or the Mendix Windows Service. Configure your Windows XP Firewall so that the Mendix application port (8080 by default) will not be blocked.
This is not a Mendix issue, it is a networking issue. Open a command prompt on your XP VM and type in ipconfig. It should give the IP address of the virtual machine, probably in the 192.168.149.nnn range.
try connecting from the host machine using this IP address, like http://192.168.149.123:8081
Edit: In your original post you say ' I already configured the port forwarding in the host for MySQL, Apache, SSH and Oracle...' Then you say that you can access this Linux VM through localhost on the host machine, so this must be your port forwarding I guess. Could it be that your requests to the XP VM are also being forwarded to the Linux VM?
Each of these VMs must have its own separate IP address or they would conflict - you should be able to access them from other machines via their own IPs rather than having to do port forwarding from the IP of the host machine.