wireless networking problem

[Gerhard Magnus]

I'm at my wits end trying to solve what I keep thinking is a simple
problem.

My old DSL modem doesn't have a wireless interface. It's connected to a
router (the LAN gateway) which then has ethernet connections to my
boxes. All of these computers use static IP addresses. The DSL modem is
assigned a dynamic IP address by my ISP. 

I recently added a DIR-615 D-Link wireless router which connects to the
gateway router. I also have a netbook which I first configured with a
static IP address and the IP address of the gateway router. This worked
fine -- but, of course, I mostly use the netbook away from home, so I
reconfigured it to accept a dynamic IP address from whatever Starbucks
wireless network I'm connected to. 

So now the netbook works fine, as long as I'm NOT connected to my own
LAN. When I'm at home connected to my LAN on the netbook I can get to
all the local computers fine -- but I can't reach the Internet.

The wireless router has an Internet --> WAN page in its setup that
includes a choice of Internet Connection Types: (1) Dynamic IP (DHCP),
which I can't use since the DSL modem has already taken the one IP
address assigned by my ISP;
(2) Static IP; (3) PPPoE; (4) PPTP; and (5) L2TP 

Will any of these work? I'd appreciate some advice before I rush in and
start changing things without knowing what I'm doing...