Keeping active in the winter

pics in this post were found with Google images

Now that we have our little home in the country with the ponies right in the backyard I won't have to spend most of my "free" time in the winter driving back and forth from the boarding barn to take extra care of Cessa. 

Don't get me wrong, it does still take a lot of time to take care of her.  Its worth it though :)

Add to that the loads of outdoor space (not quite 80 acres) I am hoping to find something 'outdoorsy' that I can do this winter, at least when its not too darn cold! 

Two things came immediately to mind, well three but snowmobiling isn't exactly 'exercise' lol.

1: cross country skiing

 2: snowshoeing

Here's the thing though, I don't really know much about either of them.  I guess I could do some research (hello Google! lol) and ask at the shops for things such as fitting of equipment. 
But what I'm more concerned with is can I do it?  For example:  Will either of these hurt my bum knee?  Or aggravate my bad back/hips/shoulder?
While neither of them are as expensive as riding the equipment isn't exactly cheap enough to toss in the storage shed if it doesn't work out...
So, does anyone out there have any input?

PS- does anyone else have this weird little square "photo video deleted" box showing up on this blog?