You are getting downvoted without explanation here. It's a reasonable thought except for a few things. First of which is our space launch and delivery systems aren't 100% reliable. Even one failure means nuclear debris spread over a wide distance - something that would be very difficult to recover from.

I couldn't find a good document from a quick googling, but this was high on the list: http://www.spacelaunchreport.com/log2013.html 81 launches and 3 failures. I don't particularly like those odds.

Aside from safety, there's another insurmountable obstacle to space disposal: cost. You may not appreciate just how much spent fuel there is. I did the math once. Launch cost per pound, times number of pounds of waste, came out to over $1 trillion. Orders of magnitude away from feasibility, even with advancements in launch technology.