I have several 25+ yr old textured ceilings. I have learned the hard way not to paint. Because there is not a lot of foot traffic on these ceiling-- I've simply "cleaned" them-- specifiically, every-other-year I might GENTLY brush the ceilings with a feather duster. I will suggest 2 options for your situation: FIRST, the ideal and the probably the most suggested option that would be suggested by readers of this forum: (1)scrape all texture off of ceiling, (2) hire drywall contractor to put a skim/finish coat drywall mud on ceiling (do not re-texture ceiling), (3)paint, new flat surfaced ceiling. If you are sufficiently turned off by the time, mess and expense of the above, ideal, option, here's the SECOND option: (1) take a soft brisseled (sp?) broom and GENTLY (key word gently) brush dirt and loose texture from ceiling ---I said "loose texture from ceiling" I did NOT say, brush all texure from ceiling! (2) put away all paint brushes. (3) Get a number of deep nap paint roller covers. (4) fill you paint roller with enough paint so that you can cover an area of the textured ceiling without having to continously go back and forth over one area--in other words, don't linger too long in one area (or you'll be pulling texture off the ceiling)---have enough paint in you roller so you can cover an area and move on--e.g., don't try to cover a 5 ft sq. area with one filling of the roller! (You'll get the hand of it.) Yes, some texture will still come off onto the paint roller--- and at some point, you will need to put on a new paint roller (don't expect to paint a 20 X 15' ceiling with one paint roller!-- it might take 4 or 5 rollers). Try this option on one of your smaller ceilings--- if you like the result, then, beside saving loads of money, there is a positive point to this approach--- in 10 or 15 years, when you want to re-paint your ceilings--- it will be a snap. That is, the texture of the ceiling will have been encapsulated in a coat of paint (your 1st caot), so, texture won't be falling off when you re-paint. Good luck. Jaes.