Clutch petal stuck in down position

I have a 92 Honda Accord wagon with 122,000 miles that has been sitting under a car cover for the last two years because the exhaust system was "shot" and rusted through from the CAT back.

But with gas prices going up and down so fast, and so expensive, I decided to let my restored 1989 Mercedes 560 SEL (12-16 mpg) sit for awhile and drive the 92 Honda Wagon (21-28 mpg)

Before I started it up again, I flushed the motor, and I replaced the tires, brakes, battery, exhaust system, filters, hoses, belts, oil, etc. It started up fine last night, so I moved it and parked the Mercedes in its place today.

Today, I went out and got in the Honda to drive it down to register it and get new plates. It started right up again, but the clutch petal is stuck down by the floorboard and won't release. I did note yesterday, before I turned it off, that it was shifting strangely, but it was shifting.

I've checked the clutch cables, wires, etc. But can't see anything wrong. Its a five speed stick, and it shifts O.K. Right now, but the clutch will not disengage.

Any suggestions?