Shallow,

Throw the Miele on Craigslist for $150 and take the first $100 that comes your way. You definitely want to ditch that because full suspension, especially old, cheap FS, is inefficient for road work and what you need.

If you can afford to buy new, start looking at the "urban" bike section, stuff with flat bars and larger, 700c wheels. Basically, this will give you a fast-on-the-road, more stable steering, heads-up riding position with brakes and shifting at hand, which is a great combo for city riding. There will always be divergent opinions on that matter from folks who prefer drop bars, but ignore them.

While you're shopping flat bar 700c bikes, keep a careful eye out for bolt holes used to mount racks and fenders. Unless its usually dry where you live, you'll want fenders, and you'll definitely want a rack onto which you can attach a bag, called a pannier, for carrying your books and groceries. You may even want two panniers so you can get the value pack toilet paper. I hate running out of toilet paper.

Lots of these urban bikes come with disc brakes, which is great, but you shouldn't kick one out of bed if it has V brakes (especially if you life somewhere arid) because they're really quite trouble free and very good. I'm guessing you are remembering wrong, and actually had cantilever brakes on your old bike. Those where a futz-fest.

Ride whatever tire comes on this bike, it'll be fine. As you start to ride more aggressively, you'll realize you keep going down on that dirt corner because you don't have any grip and will get cyclocross tires, or you won't, and will keep the kind you have. Tires are easy to change, and not a major factor in initial purchase, IMO.

Another type of bike you might consider is a mountain bike, especially a 29er, but at lower price points they're heavy and clunky, and in all cases sporting more tire than you need and generally not ready for the commuter basic rack-n-fender kit, but there are exceptions, and you'll be able to find an appropriate 26" mtb if you look hard enough, but I don't see why to bother if you don't have real off-road ambition. Besides, chicks nowadays dig the urban style bikes more. If you're a girl, Shallow, get an mtb for attracting dudes, and if gay either sex, stick with the urban.

The fact is, with enough cash and enough dicking around you can make just about any bike suitable to your needs, so don't get stressed out about any of this. Once you've set a budget-- which I'd put at $600, btw-- that will make the path you should take clear. All you need is a bike to get started.

Hope that helps.