K.C.
Make sure you have your job lined up before moving. Don't count on the jobs necessarily being there. THAT would be the main concern.
As far as your kids are concerned, kids adjust. Especially ones that are that young. 1st grade and preschool? They're JUST starting their schooling. They will make new friends and they will adjust to their new schools. This would actually be the least of my worries.
We moved from Denver, CO to the suburbs of Philadelphia, PA when the kids were going into 6th (yeah, we moved our Autistic son to a new school for his first year of middle school), 3rd (our daughter left behind her best friend) and 2nd (again, lots of friends left behind). We moved from our beloved house we'd built to a rental (which was still nice, but didn't compare to OUR home). We chose to move to be closer to family, but we made sure my husband had a stable job first. We've been here now for over 5 years and absolutely love it. We've bought and remodeled a new home, kids have more friends than they can count, *I* have more friends than I can count, husband's job is great and he LOVES it, life is really, really good right now. Every once in a while, we ask the kids if we should move back to Denver. Every time, they say "no way!". We loved, *LOVED* Denver, but THIS is our home now.
Guess how long it took the kids to get used to their new home, new schools and make new friends. Took about a week. A WEEK. Kids adjust amazingly well. Make finding a job the priority if you truly want to move.