Windows 7 and Mac 10.5 network file sharing

Question

I am having extreme difficulties sharing files over my home network! I have 3 PCs and one Mac. I have tried the Mac forums and the Windows forums, to no avail.
On the Mac side:
File Sharing is ON, with smb
Users are set to Everyone with read/write privileges
WINS has the correct Workgroup name
Network Name has no spaces in it
Shared my Desktop, Public Folder, Documents, and Shared folders (just to cover root folders and specific ones too)
Mac gives an smb://xxx.xxx.x.x address and a local network accession "mycomputername.local," but I don't know what to do with either of these things. When I put the addresses into the Windows Run dialogue box or in Internet Explorer, they don't seem to recognize the path.
Firewall is set to Allow All Incoming Connections
Under the Shared location in Finder, I can see my router name, and if I click on it, I can connect. No password is required. I am connected as my account name. However, I can't see the PC or anything at all, in fact.
Under the Shared location in Finder, I can see my shared name for my Mac. But I cannot connect to it, probably because I'm connecting from my Mac.
It would be nice to use the smb://DNSname/sharename or the smb://IPaddress/sharename function in the Go to Server window, but I have no idea where to find this information on my PC. Or on the network. Or whatever this is referring to.
On the PC:
Sharing is NOT password protected under Advanced Sharing Options
I am sharing my Desktop and My Documents with Everyone and Guest, and Windows 7 has provided a file://computername/Users/foldername path. However, when I put this into the Connect to Server or Connect to File window, there is an error.
I can click on my Mac computer name in the Network window, but I get the error message that it cannot connect (network path cannot be found, using \\MYMACNAME as the path). This is when my Mac says it is "connected" when I click on the router in Finder's Shared places.
Of course both the Mac and the PC have full connectivity to the same network.
Also, I have disabled the internal firewall in the Belkin router.
Also, my accounts have identical names with no spaces.
My Mac (10.5) DID successfully connect to Windows XP before I upgraded.
Any advice? Thanks guys!!
P.S. -- I have also posted to the Windows people here: http://social.answers.microsoft.com/Forums/en-US/w7network/thread/b5144e55-d024- 401c-85ae-1cf94226b786
In the hopes that I will double my chances of getting an answer.

Answer 1

And my response:
Okay, so here's what I've done:
OS X: did the sharing thing, smb thing, and directories thing.
Win 7: Network sharing settings are correct for Home or Work (current profile). I left my Public alone, but verified that my network is recognized as a Home location.
User accounts exist in both the Mac and PC. Names are the same. Heck, passwords match and I'm logged into the same account on each computer, just in case.
Firewalls are scary to me, so I did the best I could. I went to my browser, typed in my router IP address, and went to the DHCP Client List. Both of the computers were listed with their assigned IP addresses. I "reserved" those IP addresses so they the router would always assign that IP address to that MAC address (so I could count on it in the future). It turns out that they are sequentially assigned, so I figured that if I added any more devices (my other PC, the PS3, etc.) those IP addresses would just be +1 to the last digit cluster in the IP address.
Then I went to Windows Firewall, because I don't have a third-party firewall. I confirmed that I was connected to the Home network, and then clicked Advanced Settings. Wow, there's a lot of rules! There were multiple File and Printer Sharing rules (both inbound and outbound), so I didn't mess with them. Instead, I created a Custom Rule (bot inbound and outbound) for all programs, any protocols and all ports, and added the IP address range (192.168.2.1 - 192.168.2.9, giving myself plenty of extra for future devices) I found from above to the local and remote IP Address boxes. I specified to Allow the Connection for Domain, Public and Private, and gave it a name that started with A so I could find it easily in the future. Finally, I set the Interface Type to be LAN and Wireless (my PC is wirelessly connected).
In OS X, in the Firewall tab of the Security preference, I set it to Allow all incoming connections. File Sharing (SMB) is the first name on the list, but I cannot click on it or modify it in any way. I don't know what else to do. Am I missing something?
I've shared My Music and Desktop on the Win 7 for Everyone (not just the Homegroup!), and shared My Documents and Desktop for Everyone to read/write on the Mac.
Okay, now I need to reboot on both computers. brb...
Wow, definitely don't reserve any IP addresses on your router! I took that setting off, restarted everything, reset the modem and router, and I can now connect both computers to the internet.
I can still connect to the Windows via the Connect to Server dialogue and smb://AJPC.
In Windows Network, I can now see my Mac user account name, but when double-clicking on it I get the error message "Windows cannot access \\ComputerName. Check the spelling of the name. Otherwise, there might be a problem with your network. To try to identify and resolve network problems, click Diagnose." Under "Details," it says Error code: 0x80070035 The network path was not found." When I diagnose, Troubleshooting can't identify the problem.
Any advice? Thanks for your help guys!
A side note: I just checked my router's DHCP client list, and my PC is now connecting at 192.168.2.8, which is definitely not sequential. Good thing I specified the IP Address range all the way to 192.168.2.9 just in case; apparently the router can't count.