Why the car is parked from 2 yrs anyways? Use it if uv bought it or better sell it?
Washing is the only solution we are looking here.. get a hose pipe, without applying much pressure wash the car.. when most of the dust is gone, use a shampoo to clean it.
Dry it quickly... u can use ur electric blower after washing to get rid of water gathered at unreachable places... (u seem too cautious about rust)
Apply some good quality wax.. better use a sealant and then use the car if uv bought it!
Any sort of blower usage, dry dusting, spray wax detailer would result in swirl marks... a lot of em! Ruining ur car's paint finish...
So water is the only sol.