network accessing is very slow from the client( windows XPsp3) to windows server 2003

hi,

   i have a problem regarding accessing network. when i access windows server 2003 from the client( windows XPsp3) by accessing \\computer name of the server 2003 it doesn't come at all. actually i have shared folder in windows 2003 server. so i need to access that folder to all the computer from the client side. in client side, when i go to run and type the ip address of windows server 2003 to access, it doesn't access or that logon screen comes very late or says that \\computer name is not accessible..........................when i ping the windows server 2003 from the client side it respond properly by saying reply.... reply...like this what should i do to access fast from the client side. usually the logon access screen comes faster but now what happened suddenly. either it says that \\computer name is not accessible.................... or the logon access screen comes very late say 5 to 10 minutes. pls give me some solution so that i can access faster from the client to the server. is there any services stopped or need to be started in the windows server 2003.plz give me solution . im in trouble. thank u