2000 watts is nowhere near big enough. I've got a 2800 yamaha and when running the fridge by itself, mind you with 10/3 extension cord of 14 foot, the gen will idle to it's rev limit when the compressor kicks on. Once running, it settles down to a normal fast (3400) idle. Keep in mind that the idle speed on this thing is dependent on wattage output, at 2500w it's running 3400 RPM. It will run 4000 to turn a high load item on (such as a compressor). Just to the run the fans, it barely sweats, but once the compressor is on, it's gonna take some juice to maintain it-much less start it.
You never want to get a gen that is "barely big enough". If you need 4000w, get one about 6500. For one reason, barely adequate is a great way to kill the appliance AND the generator, particularly on cheap chinese generators and inverters. The cheap ones are cheap because of the circuitry and control system, particularly on the control boards of the inverters. On conventional generators (non inverters), the frequency (hz) is adjusted via engine RPM. Sensitive electronics-basically anything these days-can easily get fried if the frequency is "off" even just a little. That doesn't even take into consideration the voltage-which also changes with RPM on cheap generators. That's why inverters are FAR superior. That and fuel usage...most inverters vary the engine speed through the control board assembly, based on load. No load=slow (and quiet and fuel sipping) idle speed. That's why I mentioned my little 2800w gen's idle characteristics.
An electric space heater may pull 2000w by itself...I have a "little big heat" I keep in the trailer for those cold race days, and it's 600w by itself.
Also many don't consider ambient temp. The hotter the air temp, the more wattage the appliance is going to draw. Heat=resistance and resistance means more watts required to run that appliance than it would if it was cooler.
Extension cords also affect wattage requirements. The longer and smaller the conductor, the more wattage required.
Take your appliances, figure out the voltage and amperage requirement. For instance if the microwave uses 5A at 125v (usually a sticker on the back), you multiply them to get the wattage requirement. In that example, 625w. Add 10% for safety margin and round up to the nearest whole number (700w). Just used as examples, FWIW.
You can buy a little doohickey called a kill-a-watt which tells you the exact amount of wattage, I have one at work for customers that want to buy a 5000w gen to run 4800 watts.. (for example)...and most times their "estimated wattage" is FAR less than actual. This little tool has saved many a customer from buying a generator that is way too small, but there's been one or two who nobody could tell them anything different, and they bought a gen, to turn around & come back the next day saying something is wrong with their brand new expensive generator because it keeps tripping the overload. Those are the ones that are hard to reason with.