AFAIK, yes. Internal's are all standard size, as opposed to external. I'd recommend getting at least 4x speed for both DVD-R and DVD+R. Dual Layer and Light Scribe drives seem like fancy features that never caught on.
Almost all of them will support dual layer now. It's not a fad, it's just the ability to burn higher capacity discs.
If you're doing any kind of backup (especially if you're "backing up" movies from Cockbuster with extra features and shit or certain PS2 games), you'll want the DL. The discs are a little more expensive, but you'll only use them once in a while.
try not to pay too much on ebay bh,
I picked up a new lg dual layer dvd burner that does everything for $60 at a store downtown. internal drive, I slipped in in my old p4 desktop and it didn't even need the driver disk it came with. works like a charm. as mentioned above, the dl media is more expensive, but it'll burn standard 4.7 gb disks as well.