Winter is fast approaching, and I can't fit in to any of my old "skinny" winter clothes still -- and I also can't walk past our bedroom mirror without wanting to kick it in

These cloudy, autumn days are getting pretty grim...
Without elaborating in to a long dramatic post and starting in on my seasonal "I hate Alaska" rant....
I'm working full time and in school full time, so going to a gym regularly isn't an option, and I live in Alaska, where it's miserably cold in the winter, so running outside isn't going to be an option soon either... so I'm here looking for advice on a good in-door, apartment friendly, cardio option for the winter if there is such a thing.
I've been dying to get a treadmill for a few years now and I *really* want to become a runner (I've got the c25k podcasts and LOVE them, enjoyed them all summer long on the local high school track!), but where we're at now is in a weird area of town, on the third floor, and I'm worried about my poor neighbors below me. I've since started looking in to the potential of a stationary bike or an elliptical trainer. I'd want to work out for approximately 30 minutes to an hour daily. Are either of these options feasible? For gaining straingth, endurance, burning calories, and literally working my butt off?
Please chickies, give me some insight and tell me there's hope!! Because today is feeling a little hopeless