How to set WPA-AES?

I just bought a wireless adapter, Netgear WN111. I installed the driver fine but couldn't connect to my router. The adapter found some wireless networks in the neighbourhood and one of them is my router but it just couldn't connect. I played around with it (uninstalling the dirver and then re-installing it etc) for almost 2 hours with no luck.

Then I went to Control Panel --> Network & Sharing --> Connect Network. I was surprised to see that Windows 7 didn't see my router (but it found any other networks WN111 found). There was one network called something like "Virtualprofile" but it was crossed out. So, there must be something wrong with the Windows 7 settings not with the wireless adapter.

I looked at the property of the "Virtualprofile" and I noted that the network is "WPA-PSK" with "TKIP" encryption. My router is set at "WPA-PSK" with "AES" encryption. I changed the encryption to "AES", clicked "OK", then there it was it showed "connected". I tried the internet explorer, and yes I got my internet going. What a relief.

Now the problem is everytime I swith off the PC, the encryption goes back to "TKIP". So, I have to change it again. I couldn't find a way to make it permanently changed to "AES". Can anyone help me with this? Thanks.

As I have mentioned above, in Windows 7, I did change it from "TKIP" to "AES" but it just keeps coming back to "TKIP" when I switch the PC off. My question is how to make Win 7 setting stays at "AES"?

I am sorry if I don't understand your answer. Yes I can change the router setting from "AES" to "TKIP", but that is not what I want. I want to keep the router setting as is (at "AES") and set Win 7 setting to comply with the existing router setting. It just that somehow Win 7 setting keeps coming back to "TKIP" when it boots up.