Connecting to a Linux Box from Windows XP

All the while I thought that using Linux would be easier, especially if I use it as a server, but then again, I was wrong. I can't seem to see my Kubuntu box from my WinXP machine. Now I am forced to transfer files from XP to Kubuntu manually, as in, putting files on a flash drive and then moving it into the Kubuntu box. What a way to network machines huh? I guess, multiplatform network is not yet as easy at it looks, not time for mainstream yet!