Well, remember that there is technically no such thing as "Garner schools", just "Wake County schools". However, the new Board is moving toward neighborhood assignments, so being in Garner would likely put you in the Garner schools.
I love North Ridge, but I am biased since I grew up in that general area, went to NR Elementary, etc. You don't say how old your kids are, but if they went there (and it's walkable, so I'm sure they would), you should be just fine with NR Elementary (my ex-neighbor, who attended NRE with me in the 1970s, has kids who go there now and is on the PTA and she still loves it.). The commute to NCSU wouldn't be fun, but you'd get used to it and there are many shortcuts you could take if one road were blocked due to an accident, etc. Falls Village and Sutton Square shopping centers are extremely convenient to North Ridge. If they liked NR Elementary but you wanted to opt for private schools in Middle School, Ravenscroft is VERY close (I also went there, so 'full disclosure'
). You could be squirrling away the $$ for Ravenscroft while they were at North Ridge
Garner would be much closer to NC State and as you say, have a great yard. Not sure about the schools, but since you mention private schools, I don't know of any well-known ones that are near Garner, so you'd have a hike to school, perhaps. Garner is definitely more of a "blue collar" kind of town, which many find refreshing. North Ridge is solidly in affluent territory and may have more of the Keeping-up-with the-Joneses vibe there.
I dunno--make a list of what is nonnegotiable, what is important, what is desired, and what is not as important, and compare each item in both places.