Virus...pls help

[aditarya]

Hello Dear Friends,

I found my system full of virus when i came back today to the office in the morning. i have kept my system on yesterday for downloads and since it is on lan it has affected all the machines in the lan. There are almost 13 computers connected to the lan. Now after i came to office i ran a system scan in all the computers with Symantec Antivirus,but that failed to clean all the virus and the viruses have been qurantined now. My question is that can these qurantined files create any other problems to my computer.should i format my system and reinstall everything. but there are a lot of files in my computer which is very useful to me. I am really frustrated and i dont know what to do.Can anybody help me telling that is there any way we can delete all the qurantined files and will it create any problems later on.. I need help desperately...

Thanking u all in advance..