I am considering a NC mountains trip with my wife and 2 small children. We would like to rent a condo or stay in a suite. We were thinking about Blowing Rock, Highlands, or Cashiers. Any suggestions?

My vote is for Blowing Rock because I think there is more to do around there that would interest children. Grandfather Mountain should interest them because I recall several activities just for the youngsters.
The Tweetsie Railroad is a blast - literally. http://www.tweetsie.com/
Then there is the Blue Ridge Parkway, with Price Lake and the Moses H. Cone center within a short drive of Blowing Rock. Linville Falls is/are not too far down the road. The falls are scenic and the trails are quite easy to walk.
Blowing Rock itself has auctions (or at least it used to) in the evening. The children might be too small for any appreciation of an auction, but it is amazing what 5 year old youngsters pick up. It is even amazing what 2 year olds pick up in about 2 seconds. (Usually items you rather they didn't!!)

Haven't been to highlands or cashiers but i've heard good things about both. Have been to Blowing Rock and Grandfather Mtn. I liked Blowing Rock. Grandfather Mtn was enjoyable too but I was staying at someone's house there. It is a quiet place I would say. Relaxing and very beautiful. Blue Ridge Parkway is very beautiful.

I was in Blowing Rock yesterday, ahhhh. The other two replys did a good job telling you of many of the wonderful things to do(auction is gone).
We have a place at Chetola and it is beautiful. Small lake with a variety of little boats to use. Indoor rec center, breathtaking setting, adjacent to Moses Cone Park and a "maze" of hiking trails. The villiag is a quaint as they come.

I would advise against Highlands. It's a beautiful village, but very geared to adults. Cashiers is lovely. We like to stay at Fairfield Sapphire Valley. But don't go through them for a rental--go through a local realtor for a better price. It is a large resort with lakes, a pool, miniature golfing, children's program. fishing etc. Lots of easy hikes in the area. Blowing Rock is our absolute favorite. We love to stay at Chetola. They have an indoor pool, children's program and fishing. All of the units from hotel to condo are beautifully maintained. The village is absolutely wonderful. There is a little park downtown that the kids enjoy. Contact their chamber for more info.