Hey Jo,
I switched from MTBing to road biking last summer. Never had a road bike before. What bothered me at first was the different hand position. Very uncomfortable. But now it is natural and not uncomfortable. Only took a couple days to adjust.
Another thing was when I stood, the front end wasn't stable like a MTB- much more wobbly. But I got used to it, and also found that where I centered my weight when standing greatly affected the skitteriness.
Not having suspension took some getting used to. Skinny tires took some getting used to in terms of being afraid of stuff like RR tracks.
What a difference, though. Like riding a race horse after you'd been on a mule. (Not meaning mules are _bad_, just they are more like the ATV of the horse world!)
Have fun, sounds like you got a great deal, what kind of frame is it?
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson