This is from the Microsoft blog, but does a great job explaining how to set up your Windows 7 computer to stream via DLNA. I use this all the time with my Captivate via AllShare, and I hope you can enjoy it like I do.
Media Streaming
There is a new “Stream” menu prominently displayed in the Window Media Player user interface (see figure below) that exposes simple scenario-based configuration options. These options allow you to:
1)Set up your home PC so you can access your media libraries while away from home
2)Allow other Windows 7 PCs and devices to push media to your Player and control it
3)Quickly authorize all home PCs and devices to access your media collection
Each of these scenarios will be discussed throughout this post.
HomeGroup introduces the concept of “shared libraries” for music, pictures, and video. As described in a previous blog post, these shared libraries are accessible from within the navigation pane of Windows Explorer and Windows Media Player, and from the “shared” view of each media category within Windows Media Center (see figures below). The scope of these libraries is the same from each of these views.
Windows Explorer will automatically discover and provide access to shared media libraries on other HomeGroup PCs. In addition, Windows Media Player and Windows Media Center will automatically discover shared libraries from:
1)Windows Media Player 11 and 12
2)Windows Home Server
3)All DLNA compliant media servers (Samsung AllShare devices)
Who Can Access My Shared Media Libraries?
A HomeGroup is a secured set of Windows 7 PCs that can view and consume each other’s media seamlessly. Sharing is automatically set up among HomeGroup PCs and HomeGroup settings allow you to choose what types of media you would like to share; for example, you may choose to only share your music library and not your video or pictures.
In addition to all HomeGroup PCs being able to access your media, it is easy to allow devices to access shared media libraries on Windows 7 PCs. This can be done conveniently from either HomeGroup settings or within Windows Media Player:
You can also choose to restrict which specific PCs or devices have access to your media by choosing “more streaming options…” from the Windows Media Player “Stream” menu.
After this you just need to make sure the folder that has your videos in it shows up in Windows Media Player. This is a simple Drag and drop procedure. I find that I sometimes have to manually add some new content.
At this point you just go into your AllShare on your Captivate and you should be able to navigate through to your videos.
Let me know if you have any questions on any of this and I'll be happy to answer them. Also, if someone wants to post details on how to do this with Windows XP, Mac OSX, or Linux, I'll be happy to add it to the post.