High idle, stumble on accel, now won't start

Hey guys, need a little help here. Have a stock 94 GT vert, with about 83,000 on the odometer. Last night came home, and when I put it in park (aode), the rpms jumped to 1500-2000 range and just hung there. Blipping the throttle didn't do anything. I shut it off, and now it won't start at all. I have been having an intermittent Check Engine light for a couple weeks,and was planning on looking into it when the weather wasn't sub-freezing. Any ideas on where to start? The last time I had a problem it took me a long time & a lot of money to pin it down. Then I found this site & pinpointed the problem right away. You guys are all the BEST. Hope someone can help on this one... Thanks in advance...

-Mike-

Ok, here's the latest... Got the car to start. But it ran very rough for the first minute or so, almost like it was missing on a couple cylinders. Then it smoothed out and the rpms climbed back into the 1500 range. Any ideas would be appreciated. Thanks!

-Mike-