What to wear?!?!

Thanksgiving is coming up soon! Time to loosen those belts and make room for some good food!

Anyways, its my first holiday season with my boyfriend, which also means spending some real, quality time with his entire family. It's a little nerve-racking if you ask me!

I really need/want to make a good first impression on his old-fashioned, country family. And while this is mostly up to me, I could use your help on something... my clothes!

I was thinking of wearing a pair of khakis that I own that are similar to these. I have other khaki pants, but these ones are probably in the best condition.

Bayside Twill Pants, Plain Front from L.L. Bean

My question is, what do I wear on top? I want to get a pretty sweater, maybe one of the LC by Lauren Conrad tops from Kohl's. I really love all of those. But I feel like they won't go together. I really like this one: 

LC Lauren Conrad Rosette Sweater from Kohl's

I also really like this one, and think it might match a little better. And then I can wear maybe a plain white t-shirt underneath with a cute necklace? Yeah, I'll probably go along that route.

LC Lauren Conrad Open-Front Cardigan from Kohl's

Problem that I'm having is that because the waist on those pants is so high on me (and I'm so short) I'm scared that whatever top I wear, might look unproportioned, and it doesn't help when I'm heaviest in my waist either. Need to hide that fat! And I'm only used to wearing a those pants with a work shirt, so I'm not used to wearing them out.

And then the shoes!! Oh, what to wear on my feet!! Oh, the decisions!

Do you have any other ideas as to what I should wear? Seriously, what would make a good impression to a laid back, country family? I know that just about anything would, but I want to make sure!

Thanks for all your help!