obviously, i don't want to drink cold merlot. i'm just worried that the change in temperature might damage the wine.

Yes; you can cool wine in the fridge. Not in the freezer box though.

Take it out - let it warm - open it at least an hour before drinking

But remember - when people talk about wine at "room tempterature" they mean room temperature from a different age - closer to 60 degrees than the 70's that many people today favor. Even a red should be, by modern practice, slightly chilled.

Not if you plan to drink it soon. When people say that temperature change damages wine, they mean heavy changes over a long period. It certainly didn't hurt your merlot to be in the fridge once. Take it out, warm it to about 60F, and decant it.

No problems.

Just take the bottle out and stand it upright in your kitchen to let it gradually return to room temperature.

The cold won't have harmed the wine. Wineis a lot more robust than many people think.

also wine ferments quickly when open. at the bar i worked at if we opened a bottle of wine we threw it out 72 hours after it was open even if it was corked and still quite full