On the Holiday Frame embossing folder - love the look, but some have had issues with it wrinkling cardstock as it goes through. There have been suggested workarounds and tips to get it coming out smoothly, but just letting you know that in advance.
Core'dinations cardstock - I have used the cardstock before, but not SU's yet. I like it. It gives extra oomph to your embossing when you sand it, and is fun when you tear the edges for a distressed look. As to colors - not sure how you narrow it down. Brown looks great with monochromatic and vintage looks or with the woodgrain embossing folder (also from the Holiday mini!) or get red and it'll do double-duty between Christmas and Valentine's Day coming up.