Blender and Oblivion.

Hello, completely new to the forums, so please be gentle.
Right I am a modder for Elder scrolls Oblivion
and am importing some Motion capture animinations.
I have converted the acf and acm files to a BVH file that blender can read.
I have imported the file and saved it as a .blend
this is where I hit a small problem.
the x/y/z needs to be rotated.
the head is on a y axis instead of on a z axis.
it makes the animation perform as if the skeleton is lying down instead of standing up
Is there any way I can change the rotation of the skeleton without redoing the animation?
an can it be explained as If I am an idiot? (I looked at the tutorials but I just don’t learn well that way.)
Thank you for any assistance

perhaps parenting all bones to a new bone, then rotating that new root bone.

What is the source for the acf and acm files ? Was it from the game ? If so you might not want to change the Y-up orientation of the animation to conform to Blender’s Z-up default views . You might wind up with problems when exporting to the game … Though this is just speculation on my part since I haven’t tried it myself .
Otherwise you should be able to take the armature created and just rotate it 90 degrees to have it point up to the Y axis and Crtl-A (apply scale rotation) and you animation should work .