Our dining room has bumpy textured walls. We've painted them, but are getting tired of the texture - it's very limiting - can't use a border or wallpaper. Any suggestions short of sanding the walls? Would applying textured paint to fill in the low areas (fairly large between bumps) help? Any ideas are welcome!

I just removed wallpaper from my kitchen (fun job) and found that about 1/3 of the walls have had the sheetrock replaced. The wallpaper was applied directly to this bare sheetrock, but came off relatively cleanly. The remaining 2/3 of the walls have some paint. I plan on painting everything, and want to prime the entire walls since I've done enough patching work on the previously painted areas that it would probably look more uniform. My question is what type (latex, oil) of primer should I be using? I would think you should avoid any water-based product when working with bare sheetrock paper, but can you use an oil-based primer and paint the finish coat with latex? Thanks a lot. -12VMan