Finder randomly pauses on listing directory content from SMB shares

I couldn't stand the old Windows machine I have at work so I bought a new Mac Mini and brought my old Mac Mini into the office and plugged it in. It was a more or less painless process, even though there is no chance of any support. I had to sleuth out the address of our SMB network server, but I stumbled on it quickly and was up and running in about 10 minutes, start to finish.

One weird issue recurred though: sometimes when I opened a folder from the Windows network's SMB share, my Mac OS X Lion finder would display the directory contents instantly; other times, however, there was a long pause, maybe 10 - 20 seconds, while there was a "spinning wheel of lines" in the lower right corner of the Finder window, showing some work was in progess. Eventually, the directory listing would be displayed normally every time. This happened completely randomly. Once a directory's listing had been displayed in Finder once, it did not "pause" the next time I navigated to that directory.

I stumbled on this discussion:

https://discussions.apple.com/thread/2172049

and may have stumbled on the answer, although it seems to be the reverse of the solution noted above. That thread theorized that pauses were the result of a buggy DNS lookup on the Windows server and suggested using OpenDNS. I was already using OpenDNS though (specifically, encrypted OpenDNS) on my Mac Mini. I turned it off, and *boom*, Finder started displaying my Windows SMB share directory listings instantly.

I searched far and wide for an explanation for this, and the thread above deviated from my apparent problem enough that I wanted to post this here in case anyone else suffers similar issues.