I’ve encountered this a million times.
Once you’ve saved the blend in 2.5 (i use 2.53) then you cant open it in 2.49 (or less) without losing the animation data.
Does anyone know of a way to get past this and load the animations into 2.49?
Nope. The animation system is completely recoded, the devs have no plans (AFAIK) to support backward compatibility for animation over the 2.5 border. May I ask why you want to open it in 2.49 or less?
great… well, i had one problem where 2.5 renders differently than 2.49 (mostly because of lighting) and i liked the 2.49 render more. (there were also some other major problems involving artifacts due to ztransp, but those are fixed now)
thanks though.
your just more use to 2.49s render, 2.53 is faster though 
Maybe if you uncheck the color management (in render->shading) feature it will look more like the 2.49 render? If you’ve built your scene in 2.49 and adapted it to that light/color conditions then it’s going to look a little different if is suddenly rendered with color management in 2.53.
Use color management when building a scene from the start in 2.5x, or at least if you do lightning + rendering there. It is really what you want, with correct gamma and whatnot.