I use Jasc Animation Shop 3.5 for opening .gif images, and PSPX and PS CS2 to open just about everything else.  What I'm wanting to do, is set it up so only animated .gifs will open in AS (Anything with multiple frames) and regular .gif images (ones with only one frame) will open in PSPX.  Is there any way to do this?

No.

However, if you have any programming skills, this could be accomplished by a simple executable program with no user interface, which would be set as your default GIF handler and simply ran one of the two programs you mention, depending on whether the GIF file consisted of single frame or multiple ones.

Otherwise, perhaps someone here has time to make one for you -- unfortunately, I do not.

I wouldn't even know where to start on that.

use your registry, it controls the programs that manage the file extension [HKEY_CLASSES_ROOT]

WARNING: a wrong modify to registry could crash your system down to unrepairable, and u MAY even have to reformat the HD, document yourself about it before going through the registry.

how is that going to help at all pedro_cesar? adeptus's idea would work.

yours at best would just change default program for ALL .gifs rather than just animated ones