I want to remove the texture on my walls and repaint. The Home Depot guy said to skim them but my concern is that the paint chips off at the slightest touch leaving a smooth white patch. Will the mud hold the textured paint on or should I sand and start over?

If the existing paint is flaking off so easily, I'd start by removing the texture. Obviously, it is not adhered well to whatever is under it(sheetrock or plaster) Take a putty knife or scrappr and try removing it. Dampen any resistant areas with a spray bottle or sponge. When all is removed and dry, sand the wall and paint.It may be a little messy, but I think the weight of the skim coat is going to pull the loose texture off the wall.
Good luck with your project-

Hello,

I just thought I would share an experience I have had with removing stubborn textured paint--when all traditional methods failed (because it had been painted over SO MANY TIMES!) as a last ditch effort before replastering, I decided to try a commercial paint stripper on my plaster walls...it worked very quickly, easily, and with remarkably little mess and no dust. I was able to do my 13 by 19 master bedroom AND ceiling in a day and a half. Unfortunately, this wouldn't work for drywall, but I just wanted to let any owners of older homes know that before calling the plasterer...this really isn't too bad. The stripper cost 15 dollars, 2 dollars for a natural hair brush, a standard paint stripping tool that you probably have laying around all ready, and three rolls of paper towels to clean off the stripping tool after each pass. Best to wear a ventilator, however. I did do a light sanding over the plaster with fine steel wool before priming the walls, too.

The other perk to this method was it rectified bad patch jobs to cracks and dents, which enabled me to go in and do it correctly. The previous owners had done poor patch jobs and then to hide their poor workmanship, put a textured paint on the walls. There weren't even very many cracks to begin with!!

--star