Where are you riding in "winter" that you don't use studded tires?

Anyways, toe-clips suck, IME they are impossible to get out of in an emergency when properly done up to the level at which they're going to help your feet stay on the pedal.

As others noted the safest is flat pedals, but if you want to be locked to the pedal I suggest upgrading to clipless - They're a lot safer than toe-clips and due to their spring mechanism they won't wrench your ankle and knee so badly if you fall accidentally.