First off, welcome (potentially) to the area and congratulations on the job! I've lived in Orange County for nearly 18 years and hope that I can be of some assistance to you. It will certainly be a bit of a transition, moving from the big City to what most NYC residents would consider "upstate" or the "countryside." The county has undergone significant changes since 9/11. Before 9/11, it was rather rural and cheaper. After 9/11, many City residents packed up and moved north, leading to the second highest population growth rate in the state (source: Census 2010). The boom in population has led to more disposable money for the county, which allows it to compete with Westchester and Rockland for NYC commuters/families. This has also led the county to become more urban or at least suburban in nature. There is also a good deal of open land around the county and in neighboring counties, something that Rockland and Westchester can't really offer, making it more attractive.
The good news is that we are still within the NYC Designated Market Area limits, which means that we get all the news stations that you are used to (NY1, CBS2, NBC4, FOX5, ABC7, etc.) as well as the prime NYC radio stations (92.3 NOW, 95.5 PLJ, HOT 97, Z100, WFAN, POWER 1051 and so forth).
The drive from Queens would be a hell of a haul and think that relocating is in your best interest. Fortunately, there is an abundance of housing in the area and I don't think you'll have a problem finding anything, short or long term. For short term housing options, I think that this is your best bet: hudson valley sublets & temporary classifieds - craigslist
or hudson valley apts/housing for rent classifieds - craigslist
For apartment hunting, Google is your best friend. I actually used to know someone who lived in Imperial Gardens, it seemed nice enough to me. Very convenient to everything in Middletown. You can search for other apartment complexes in Middletown, or search in the nearby communities of Montgomery, Goshen, Chester, and Florida. Expect to pay $1000-$1500/month to rent a decent place.
In terms of public transportation, we have Metro North (operated by NJT in Orange County) and Metro North across the Hudson River in Beacon for direct service to Grand Central. Lots of commuters to NYC, not too many doing the reverse, however. Monthly from here to NYC will run you about $400 (same from NYC out here). There is also Shortline
to/from NYC Port Authority. You'll need a car up here -- it would be difficult to live without one.
Middletown is on the major Route 17, I-84, and just miles from 87/NYS Thruway. 45 minutes to the Tappan Zee, 65-80 minutes to NYC limits by car.