painting a floor

I have a non-standard door opening with badly finished, fixed louvered wood bi-fold doors. I'd appreciate info on the best way to refinish those doors from start to end. I've been told to start by completely disassembling the doors, then sand, then reassemble, then prime & paint. Is there a simpler way? The louvers are too close together to adequately sand between them. I bought the dremel contour sander thinking it would work, but the pad is too thick. (approx. 3/8" with sandpaper) The original finish (some sort of dark stain) was applied without first sanding so the grain has raised and left unsightly (and sometimes aggressive) hairs/slivers which probably couldn't be tamed by mere heavy priming. Any help would be appreciated. Thanks.

The kitchen walls are flat because they had wallpaper removed from them before the last painting. We are getting ready to paint them again and want to add some texture so they are not flat. What is the easiest way to add texture and what do we need to accomplish this? Thanks!