Hi.
"My router sometimes is showing all lights blinking and set and internet connection is not there when accessing anything. It happens when lights go out and i restart my router or when wireless is connected before ethernet connection."
When Internet connection disconnects, if you hook up the computer to the modem by an Ethernet cable, do you still have Internet access?

If you still can access Internet by wired connection and just the wireless connection is not working, you can check this link for more information.
http://forum.tp-link.com/showthread.php?20899-Modem-Restarting-Randomly-itself-Automatically....(its-very-Annoying-me)-NEED-HELP&region=china

1. When my both wired and wireless comuters connection goes out it stays out for both wireless and wired until restarted
2. Sometimes When my laptops are connected first they remain in conncetion and wired cannot connect until router restart.
3. Sometimes When my wired computer is connected first it remain in conncetion and wireless cannot connect until router restart.

Also my router logs show these errors messages
every times i click on any website these errors are there please help.
7/25/2013 20:40:10> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:40:38> Last errorlog repeat 146 Times
7/25/2013 20:41:2> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:41:24> Last errorlog repeat 36 Times
7/25/2013 20:41:24> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:41:24> Last errorlog repeat 1 Times
7/25/2013 20:41:31> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:42:4> Last errorlog repeat 55 Times
7/25/2013 20:42:5> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:42:40> Last errorlog repeat 26 Times
7/25/2013 20:43:4> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:43:14> Last errorlog repeat 5 Times
7/25/2013 20:45:18> netMakeChannDial: err=-3000 rn_p=80543d40
7/25/2013 20:45:20> Last errorlog repeat 6 Times

Also When i see statistics i only find errors in wlan never in ethernet and adsl only in wlan error mostly recieving errors.

Since your TD-W8951ND is V5, have you tried to upgrade it by the beta firmware?
Here is the download link: http://www.tp-link.com/resources/software/TD-W8951ND_V5_Beta_130705.zip