Cannot print to network printer from wireless notebook

I have a home network based around a Dlink DI-624 router. This is a wireless router, with 4 hard wired ethernet ports. I have two desktop computers on two of the ports, and a Dell 3010cn networked printer on a third port. Everything works fine in this configuration.. that is, I can print from either desktop system to the networked printer.

The problem is that I just cannot print from a wirelessly connected notebook (Toshiba M30). (Desktops running XP Pro, notbook is XP Home)

There are two scenarios.. in the first, I try to load the network print drivers, but I cannot find the printer. So, I turn off the wireless, and connect directly via ethernet - retry the install, and it now sees the printer and installs the drivers. I print a test page, and it is ok. I remove the ethernet cable, and connect via wireless again. I print a test page and it works. However, after turning off the notebook and turning it back on, it no longer can print. When I attempt to print, it sends the file to the printer queue or spooler or whatever it is called. When I look at printers and faxes, I see the printer, ready and online, and the document pending, but it never gets printed.

The second scenario: I had suspected that maybe the problem might be related to the WPA encryption I have enabled on the wireless router. Dell had suggested I remove it and try again. I did this, and it printed fine. Dell said the printer does not support WPA encryption, which I found sort of odd. Anyway, I re-enabled the encryption, and tried to print again, and it still printed ok. I thought the problem was solved, but after turning off the notebook and turning it back on later, I find that I still cannot print - same symptoms as above.

So, I have no idea why I can't print to this printer. Is the problem related to WPA encryption? It seems unlikely, since in both scenarios, I can actually print with it enabled - it just stops once I recycle power on the notebook. Actually, power is not directly involved, since just closing the lid to put it in suspend mode and then opening it will also manifest the problem.

I notice that each time I open the notebook or power it up, I have to wait while acquiring a network address. This usually takes a few minutes, why I don't know, since I believe I am getting the address directly from the router and not my service provider. However, I am wondering if this has some bearing on the problem.

Any ideas or suggestions?