Tile flooring over AGED concrete Slab

I'm going to be tileing an old concrete slab, the slab was poured back in 1980. There are cracks in the slab, no real width to any of the cracks and no vertical movement at the cracks either. I'm pretty sure the house and slab have done all of the setteling that they are going to do. BTW, this is an old hunting cabin that never had anything other than the slab for a floor.

What type of crack isolation membrane would you use over the existing cracks? And what thinset and trowel is the best to use. I'm not worried about price, I just want the best overkill option available.

Any advice is HIGHLY appreciated as this will be the first tile job for me.

Thanks.

 http://www.schlutersystems.com/Schluter-DITRA-XL.aspx

^^^^ Cool stuff. I remember seeing this stuff before somewhere. Thanks for the link