Personally, I prefer a smooth ceiling, but texture can be good, depending on the style of the house. If the texture has been painted, you'll not get it off easily, and best to replace the drywall. But, if it hasn't been painted, it may not be that much trouble to scrape it off. Try a spray bottle with some water in it...wet an area, let it sit for a couple of minutes, spritz it again, then use a wide putty knife and see if it scrapes off easily. You might be surprised. I did an area of about 500 sq feet in a couple of hours this way. Makes a mess on the floor, though and wear a hat!
One thing I've found that can help...it's not a texture per se, but it has some advantages in that it will cover some imperfections and has the additional benefit of adding some insulation...check out
www.insuladd.com. I used it on my interior walls and, when I remodel the upstairs, will use it again, especially on the ceiling to the attic. I'll be removing the texture on the ceilings during that remodel (mostly tearing out the carpeting, putting in new wood floors, and replacing the ugly, hollow-core doors with 6-panel solid ones.