Learning to take photos inside.

First off, I don't have a super well lit house. Wish I did but, alas, I do not. Just over a month ago I got my Canon. I am trying to shoot in manual and customize my settings. This is hard for me, but I'm trying. I've found that our bedroom is more well lit than my living room. I recently took some photos of Lincoln for his 14 month old update. I feel they could have been a lot better. They were a little grainy. :(

So, hopefully I have some photographer readers. What are the best settings for inside? Some advice to getting clear, crisp photos inside?