Windows 7 - Windows 7 and XP network

Wanted to get some ideas on a issue I'm having. I have a windows 7 machine and a XP machine. Both can see each other and both can ping each other. The XP box can access folder and printer shares on the 7 machine without issue. If I attempt to connect to the xp machine from the 7 machine I get prompted for a uname/pass.

Both machines are in the same workgroup
xp machine has firewall disabled
both can ping each other
both can see each other in network places


In my research I've found that xp machines need the lltd to "see" vista/7 machines. I thought that this was included in XP SP3 which my XP box has. I have also found an article explaing how to install the lltd on a SP3 machine since the download from MS is only for SP2. Would it be worthwhile for me to follow this article from ehow?

On the XP machine perform the following adjustment which should fix the password prompt problem for you.

Goto... Control Panel > Administrative Tools > Local Security Policy > Local Policies > Security Options

Scroll down to... Network Access: Sharing and security model for local accounts

Select... Guest only and not Classic. I checked on XP machine and Guest seems to be the default.