the best thing that you can do is just exchange those altcoins to bitcoin using shapeshift,
The real problem is that shapeshift had a lot of issues during the last week, if you are not aware, i suggest you to make a better research before trying to post this exchange in here.
A lot of people started using shapeshift because it was very easy to use it, and in every website that accepts bitcoins, they were accepting altcoins through shapeshift too.
But i dont know why they scammed a lot of people lately, but i still prefer this one instead of bittrex or poloniex.