Win2K Networking Help

I have a home network that runs behind a Linksys Cable Modem Router. I have always had 2 machines running Win98 with not troubles sharing files. I have now added a new machine on Win2K. Can someone please tell me how to be able to share folders between the computers. I created a share, but it asks for a password that I did not specify. I tried the only password on the machine, the one for the Administrator, and it did not work. I tried no password, and it did not work. What is trange to me is that it asks for a password, but no user name. I can connect to a shared folder on teh Win98 Mahcines, type in the appropriate passwords for teh shares, and have no problems. I just can't get the 98 PC wo access the Win2K machines. By the way, I can ping the Win2K machine

For reference, my Win2K machine is Abit KG7, 1.4GHz Athlon, harddrive is FAT32.