Livecd & wi-fi

[writee]

I have just downloaded the 2011-6 KDE Livecd.  I booted it and set up my wi-fi connection to the internet.   I see that my signal strength is 71%.
After that, I cannot open any files or programs.   No Firefox, no Dolphin.  Everything seems to be locked except the menu and consequently the shut-down system.  Without wi-fi set up, I was able to open firefox and dolphin and see other partitions and discs on my machine.
I have TP-link network/wi-fi gear.
Any suggestions please?
Writee

[Just18]

run 'top' in a terminal to see what might be hogging resources

reboot and see if the problem is repeatable

supply some hardware details for someone who may wish to help