Brake problem

[smcinrox]

I have a 94 Toyota corolla dx with the 7AFE engine. The brakes stick sometimes when I'm driving it. When this happens, there is no play in the brake pedal. This happened to me the other day when I started it up. I started the engine, put my foot on the brake (There was no play in the pedal, it barely moved), put the automatic transmission in to reverse, took my foot off the brake and pressed the accelerator. I had to press the accelerator down quite far to get the car to budge. I then put the car in park and a couple of seconds later I pressed on the brake pedal and it felt normal (it had play, I could press it down maybe 5" and it would return to its original position when I took my foot off). I put the car in reverse again and it took minimal acceleration to move the vehicle. Put the car in drive and it went forward with minimal acceleration. While driving, every once and a while I would feel the car start to bog down and I noticed there was no play in the brake pedal again. I would keep my foot on the accelerator and tap the brakes with my left foot and I could get the play in the brake pedal back and the car would run normal again. I don’t have a real good understanding of brake systems and I’m wondering if anyone out there has any idea what may be causing this and what I can do to fix it?