virus blocks me from accessing internet

Hello , When i was accessing internet i suddenly got some pop ups ..

and since that i am not able to access internet .

then when ever i reboot my computer  - my firewall was turning off automatically .

I use symantec antivirus - scanned it but - it did not find anything

i have super anti spyware - i scanned using it - it detected soome trojan horses .

i deleted everything . then used combo fix too .

 

now my firewall is not turning offf automatically wen ever i restart .- that issue is resolved 

but still i m not able to connect to internet . the other computer's n notebooks on same network is working fine ..

 

plss help !!

i m using windows XP service pack 3

i m able to connect only using yahoo msgnr . but i m not able to access any web sites .

i tried system restore to eaarlier date - but it says - cannot perform system restore ..

Wireless connection status says - its connected - but only a few packets are transfered . and the IE shows page cannot be displayed .

even mozilla doesnt work .

 

please help out !!!

 

Thanks in advance :)