Hi,
The only reason I use BTWiFi is because I have the username/password as part of my BT Broadband package and it gives me unlimited free access which is useful if I ever get close to going over my data usage limit. Also the BTWiFi signal is slightly stronger than the BTHub3 signal giving me better results when using my Desire S around the house.
Without the username/password it isn't really an option for you.
I use Wi-Fi to connect a laptop and my Desire S to my hub so that I can use the internet over my BT broadband connection. As far as the Desire S is concerned there is no option but to use Wi-Fi. With the laptop I could use an ethernet physical connection but choose to use Wi-Fi for convenience sake.
Wi-Fi enables the use of my Desire S throughout the house, not only for web browsing and email handling but because my house happens to be in an Orange signal blackspot I can use the Signal Boost facility on the Desire S for mobile calls.
I don't understand how you are using the internet without using Wi-Fi, unless you have another computer/laptop using an ethernet connection, to access your broadband.
You say your Nexus is connected to your hub/router but I thought the Nexus can only connect by Wi-Fi, or is that not so?
If you are using your Galaxy to browse the web using your Three data package then as Argedion said, you are likely to hit your limit.
To return to your problem of the Galaxy not connecting, I don't know the Galaxy Ace at all but on the Desire S if I go to Wi-Fi settings it gives me a list of SSIDs in range with an indication of signal strength. If I'm right by the hub all three of my SSIDs show full strength (3 bars) with another BTHub3 SSID in range but very weak (no bars) which is obviously one of my neighbours.
It's from that list that I can force the Desire S to connect to a particular SSID by tapping or long pressing it which gives an action box with a number of options one of which is 'Connect to network', if I tap that option it will disconnect from the current SSID and connect to the new one.
If your Galaxy has the same or similar settings page you can check the signal strength of your Orange Hub/Router SSID and one of the BTWiFi SSIDs.
If you can do that and tell me what results you get we might be able to get a bit closer to the problem.
