Connection phenomona: another reason why...

Hey there, I have a dell studio 1535 laptop with a dell 1397 wlan mini card and a vista os. I have problems connecting to certain wireless networks but not all. For instance i can connect to specific wireless access point signals that only broadcast 802.11b or 802.11g but not both. Whenever I try to connect to an ap that broadcasts both in b and g specifically and im like inches away from the router, and sure enough far away from functioning devices that could interrupt the signal like microwaves and the rest, the Diagnosis says that it does not recieve reponse from the wireless router of access point. Mind you I am getting full bars, SSID name, the network type, security type all the on information on the signal but just no reponse for a it to connect. I've updated the BIOS and all relevant drivers, i've used F8. Doesn't work. The only way i could get a connection from network like this is to use a LAN cable and that works fine. I'd like to remind you that i don't get this problem from all wireless networks. I can connect to a few wireless hotsopt but not others. In some airports but not in others. On some home networks but not on others. I'm just look for options. Oh here's the ***** part of the situation. Earlier this year I partition my Laptop to run a Linux OS and I still have it. When im on linux I got little no problems with wireless connections. Wireless network that were in accessible to me before on vista I have access to now on Linux. It's weird to me how that works but I know its a clue to whats going on.