[Urgent] Dedicated IP for Guest OS, how can I do it?

[MKVCrazy]

Hi, I have VBox running on a Linux Ubuntu host with a Win XP guest in it. I would like to give the Guest OS (XP) a dedicated IP so when I connect to the Guest OS from another computer I don't have to enter like this. XX.XX.XXX.XXX:PORT (VRDP). But instead I would like to use a public IP that's just for the Guest OS. I have 3 IPs given by the ISP (provider). How may I use/install one of them into VBox for the Guest OS?

G - Guest's Dedicated Public IP
So that when I connect to the Guest OS, I can use: GG.GG.GGG.GGG (without any ports at end)

More info:
Host - Ubuntu Karmic Koala 64-Bit
Guest - Windows XP 32-Bit
Connecting using VRDP (null Auth.)
VirtualBox PUEL v3.1.0 r55467

[Perryg]

Use Bridged mode and set the guest to use the IP address manually.

[MKVCrazy]

I found Bridge Adaptor but I don't understand exactly how I am going to set the Guest to use that new IP. There is no field box to enter it.

[Perryg]

You would enter this information in the guest. For Windows it would be in the network settings.
You disable (uncheck use DHCP) and enter the static address information there.