deactivating laptop firewall to make router connection

I just bought Dell Latitude to replace the Acer i'm writing on now which is connected to my home wireless network.  In opening and starting the Dell, it appears it wants me to shut down its firewall to bring it on to the network.  I'm leary of doing this because the last time I shut down the Acer's firewall I was majorally infected in a short time (which is why I got the Dell).. Can I safely do this for a brief time?  Or is there another way.  Thanks to all who respond.