I went to boot camp December 22, 1999. We didn't get to do anything special for Christmas (no phone calls or anything), but it was treated like a Sunday. Basically, we had most of the day to sit around, write letters, catch up on ironing, etc. Our sister division got to spend the day out in town with an adopted family. My husband was in boot camp last year for Thanksgiving and Christmas (left on Nov 4). For Thanksgiving, he said they had a really good dinner - pie and all. He didn't get to call home that day, but they gave them their first phone call that weekend. For Christmas, he wasn't adopted by anyone in town, but his division did get to go to Recruit Heaven and hang out for the day.
As far as seeing your family, I got a letter from RTC asking if I would be in the area and would like to adopt my sailor for the day. I'm assuming that your family will get something similar if you are far enough along in training. If they live in Chicago or don't mind traveling, you will probably be able to see them for a few hours that day.
Most of your training will be done inside. You'll still muster outside and have to march to medical, chow, chapel, etc. It's cold, snowy, and icy. When I say cold, I mean cold. Chicago has pretty crappy winters, but Great Lakes is usually about 10 degrees worse than the city. You'll be wearing gloves, a watch cap and a sweater (at least we did with utilities... not sure about the NWUs), but when you stand outside for the better part of an hour waiting to go to chow, it gets really cold. In case I haven't said it enough, it's cold. You will also be standing snow watches which means that if it starts snowing at night, they'll wake you up and send you outside with a shovel. The winter I was there, it snowed a lot. In fact, the second day of training, one of the guys I flew in from MEPS with fell on the ice and broke his leg. He was rolled back for almost 6 months.
As for the road guard dominoes... LOL! Nothing like seeing one guy trip on the ice and take down a division of 80. The beating we got laughing was worth it!
Enjoy the snow though; it will be a while before you see it again! Goose Creek isn't exactly a winter wonderland. In fact, it's going to be in the 80s this week. Nothing like Halloween at the beach!