From the settings and diagnostics you are displaying there doesn't appear to be too much of an interference problem - I've certainly seen worse - but that doesn't mean there isn't something bad going on.
Before you start - standard debugging rules apply - change one thing at a time and if it doesn't work then revert to the default setting before trying the next change.
First thing I'd do is focus on the Netbook and check to see if you can force it to use only 802.11b t. If there are options to completely disable power saving on the WiFi adapter on the Netbook then disable it. Likewise if it supports any custom extensions (specifically Cisco's CCX) then disable those. You might want to change the settings and power cycle the system too, just to be certain that the changes are taking effect.
If you can't make those changes or the have no effect move on to the AP. At a minimum though I would leave the Netbook WiFi fixed in 802.11b mode with power saving disabled if at all possible. 802.11g\n operating in the 2.4Ghz band can have a harder time dealing with interference so for the sake of debugging it is a good idea to eliminate the issues that they may introduce from the equation.
Your AP is operating in mixed mode at the moment too so change the Network mode from Mixed to 802.11b only to reduce the impact of interference from foreign 802.11g and 802.11n sources. You also have quite a lot of headroom in terms of Transmit power - try boosting the Xmit Power setting, and raising the noise floor (but be careful there raising it will have an impact on potential throughput). I'm not familiar with your AP but you might have to reboot it after each change.
If you do get things to work in 802.11b mode then try switching over to 802.11n only (if your AP supports it) or 802.11g only on both the AP and Netbook to see if you can sustain the higher signal rates those protocols will support.