We ended up using the top 1/2 of a 4 lb squash (because we didn't feel like going through the work of cutting the rest). I'd say it was the perfect amount, so a 2 lb squash would be fine too. Because the squash was REALLY hard, we thought it would be flavorless, but once cooked it was great. You just have to cut it first.
HOW TO CUT THE ANNOYING SQUASH
1)peel the part you want to use: we used a large vegetable peeler.
2)cut into large block (i found a large bread knife best, but even that was hard)
3)create small cubes using a small knife.
Tips for next time: Try using a frozen boxed squash instead if fresh. I can't guarantee it will be as good because i used the real thing, but it would sure be easier. This is a very versatile recipe, so feel free to play around with it. I did! Things I changed are noted on the recipe.