Yep, it's the first weekend of winter holidays for schools in southern Finland, but that souldn't be a problem in Rovaniemi. Maybe a little bit more activity than the week before but nothing major.
For dog sledding, snowmobile safaris etc the first place to contact is either your hotel or Rovaniemi tourist info. All hotels should have good connections to safari companies and husky farms. At least CityHotel does. Just have a look what might interest you and book in advance if possible. That should save you some time.
For cross-country skiing Ounasvaara, the hill besides Rovaniemi, has some nice trails. Some easier and some a bit more demanding. For equipment rental contact SantaSport - our local sports institute. A set for cross country skiing 30€/day or 47€/three days. For skiers best sport shops in town centre probably CitySport for equipment and Sportia or Intersport for clothes.
Restaurants worth a mention Nili, MonteRosa (CityHotel), Sky Ounasvaara and Gaissa (Hotel Santa Claus). About 35-55€ without drinks. Several pizza and kebab joints. Bull Bar&Grill for big burgers and Comico for Mexican style.
Nice cafes Cafe & Bar 21 and ChocoDeli & Bakery. Antinkaapo -bakery is a more typical Finnish "konditoria". Good cakes they have.
From Rovaniemi it's only abouty 1-1.5 hours bus trip either to Luosto (cross-country skiing trails and some scenery spotting) or Ranua (Ranua arctic zoo).
What else... Rovaniemi design week starts on 18th of February. I still don't know what it's all about, but the design-dudes and arts students seem to enjoy it. I think it's centered around Arktikum.
For more sports activities you might get a glimpse of Rovaniemi 150:
http://www.rovaniemi150.com/
Last year I only got to see a couple of contestants. It's not a huge happening but hopefully getting bigger.
Ice Hockey match between RoKi (locals) and Pyry (Nokia) in Lappi-Areena, feb 16th 4p.m.