I need to clarify some of the information you have provided. If I understand you correctly, you have installed Linux on your DELL machines and now want to create an image using Ghost.
You are using Ghost Boot Wizard to create a boot image (please clarify whether DOS or WinPE) and the image you create is then giving you an error 10030 when you try to connect to the Ghostcast server.
If any of this is incorrect, please provide more information on what exactly you are doing at each step.
Assuming my understanding is correct, I can confirm that error 10030 is usually caused by NIC drivers not working, so we need to delve a little deeper into what you are doing and which drivers you are using, and what chipset the GX620 uses for its NIC interface.
For modern hardware I would always recommend using WinPE as DOS is severely limited in its support for things like SATA hard disks and optical devices, which are now pretty much standard on all new machines.
When adding drivers to Ghost boot wizard, you need to use VISTA 32 bit drivers as this is the version required by WinPE (regardless of what operating system you are imaging). Once the drivers are added, they also need to be SELECTED so that they get incorporated when you rebuild the boot image,
Let us know how you get on and whether my understanding of your problem is correct.