Slow Access to Network Shares

Hi, I have a 2003 Active Directory network and 6 XP workstations. Accessing data on the server takes a very long time especially for files. Howerver, normal connections such as Remote Desktop etc.. Also, if I login to the local computer I can access these files much faster but I need the users to be logged in to the domain. Accessing files by hostname takes longer than accessing via the IP address.

Any ideas? Any suggestions.