Very good first attempts Jann. The 2nd shot looks much better than the others. Thats because you used a faster shutter speed. If you were using the 100mm lens then the 1/100th shutter look pretty much right on. I would also definately say that the f/22 was unnecessary. Looks like f/11 or f/8 would have done fine and would give better sharpness. The 1/25th and 1/30th shutter on pics 1, 3 and 4 were way to slow thus showing the sledders with to much motion. Pic 3 looks like the shutter might have worked, but the focus was off. Your distance looks good, just maybe a different angle. Maybe instead of standing up try sitting more at the same level as the sledders and you'll get more of the background. The background blur looks great.
You certainly have the right idea, just a few minor tweeks look to be need for better results.
I haven't done panning in a while so I'm not going to say that I would have any different results.
With your focusing are you using a specific area. I don't know what the focus points look like in the XT's. I know in my D50 I have 5 small rectangles for my focus area's and can switch from one to the area. In this situation I would keep the head of the sledder/skier in either the very middle focus area or the middle-top focus area and that would just how fast I move the camera. If your already doing that then its just a matter getting the settings correct and doing a little more practice. Thus your definately in the right direction.