The only Buran that flew into space is in no better shape than Columbia.
A couple of couple of years ago the roof of the Baikonur Cosmodrome collapsed, killing eight. Also destroyed in the collapse, due to heavy rain and tons of construction equipment stored on the roof, was the Buran 1.01 space shuttle, which was being stored at Baikonur. Buran 1.01 was the only Buran that flew into space.
Another Buran, the flying prototype (similar to the American Enterprise) is currently in Australia, rotting away, awaiting a buyer (it was sent to Australia and was put on display during the 2000 Summer Olympics).
The Buran test ship used for heat and vibration tests is now an amusement ride in Moscow's Gorky Park.
More details of these and the rest of the Buran ships at http://www.ljonn.com/buran.html
Anyway, even if Buran 1.01 hadn't been destroyed, there were many differences between the Russian and American shuttles, the most significant of which was the absence of the main rocket engine on it. The Buran was boosted into space by the heavy rocket ENERGIA. By itself ENERGIA was able to place into orbit 120 tons of payload (more than enough for a shuttle like Buran). There were only a few Energia's built, and I don't think any exist today. There's no way the Buran could've been hooked up to the American Shuttle booster.