I have a vibration i'm trying to locate. Is it ok to drive with the front drive shaft removed? I would like to eliminate this as a source if possible.

Yes

yep. I did it w/ my truck for a long time. I once broke my pinion gear in my 91 toyota and removed the chunk and drove in 4wd and the rear shaft removed.

sure...you could even engage the 4x4 without causing any problems...I've seen it done by a guy who wanted 2WD LOW for some heavy pulling...just unbolt the front driveshaft and go.