There's a few different ways to use Poser animation. The easiest thing to do it make .gif animations.
After you have your animation the way you want, click on Animation at the top of Poser, then Make Movie and a new screen will come up. You'll see there's three different ways to render and save your animation.
1. Image Files for .gif animations
2. AVI for video or
3. Flash for Flash.
To create .gif animation, choose Image Files and let it render.
After Poser - Creating the .gif
.gif animations require a program to put them into an animated form. GIF Movie Gear is a good and reasonable one. It can be downloaded here: Gamani. There's a 30 day free, unrestricted trial.
First click on Open File and it will bring up a windows explorer. Go to where you saved your renders, highlight them then click Open. Rather than having to add them one at a time, you can highlight all of them and they will load into Gif Movie Gear in the proper order.
Once the files are loaded, you'll see the animation working in the Preview Animation screen. It will take some tweaking to make it look right. Close the Preview Animation screen by clicking the red X thing.
Clck on Frame then Global Properties.
If you are making the animation for a web site, change the default "No Removal Method" to "Restore to Background". Then change the timing to whatever looks right.
Single frames can be changed as well. Do this by clicking on the frame you wish to change, it will highlight in red and the frame number will show on the left side of the program. Next to the frame number, you'll see a clock icon, put he speed for that particular frame in there.
Optimizing - reducing filesize
If you wish to reduce the animation file size, there's a couple things to do. First is to reduce colors. Reducing the colors can drastically reduce the quality of an animation.
The other way to optimize is to replace duplicate pixels with transparency and shrink the frames to only what is needed.
If you need to get rid of the white space around your animation, click on Animation > Crop. It will bring up a box, pull the square sprites around the animation or use the setting boxes on the right hand side and click ok.
There are more options within GIF Movie Gear, changing the background color of the animation for instance. It's best just to click around in the program and experiement.