It looks that Win 2003 server can only see Windows XP and Win 7 Ultimate. We like to buy some newer PC but don't want to pay for Business or Ultimate. Is there anyway that Home Premium can connect to Server 2003?
Home premium doesn't work with domains, however you might still be able to connect directly to the PC.
In the address bar in Windows Explorer, type the following (replace the IP with the IP of the W7Home PC):
You'll need to know a local username and password to be able to see files.
The reverse works if they want to connect to files on the W2k3 server, though they will need to know a domain username and password.