i have little knowledge of computers

whenever i try to connect through a wireless connection (which i use daily)
my computer tells me i have limited or no connectivity.

What should i do.

i have tried to repair it
i have hit start/run and typed in cmd.exe
then typed ipconfig /release
then ipconfig /renew


but it says no operation can be preformed on LAN while it has its media disconnected
it then goes on to say that an error has occurred while renewing interface wireless network connection: unable to contact DHCP supervisor

what should i do??

note my ip address comes up as 169.254.154.193

That IP address is allocated by the OS either because it is fixed or it cannot get one from the router.
The following assumes you can get at the router using a patch cable.
Check the wireless network settings and confirm they are set to automatic
(Control Panel > Network Connections > wireless connection > properties > TCP/IP > optain IP address automatically; ditto DNS).
Check your wireless security and reenter the WEP or PSK or whatever security you are using.
Check the router wireless channel and change it - you may have a new router near you which has pinched the channel you were using.