I did the "classic" Angkor experience back 12 years ago, before Bangkok Airways flew the route and started the ruin of the place. It included the boat ride in the unsafe, overloaded boat across the Tonle Sap, leading to the pier where you'd get mobbed (literally) by guesthouse touts. Just getting transit without guesthouse stickiness was tough, and I went for a pricey $4/night one with fans and mosquito nets. Competition for the moto-driver business (paid $6/day) was fierce and usually the guesthouse owner would be aggressive in "helping" you take care of that need with someone who probably was a family member. He'd take you between sites but would sleep in the hammock when there and didn't double as a guide. Kids with precocious English skills would eagerly volunteer, but the Lonely Planet Guide was a good reference and really helped.

You didn't see much in the way of crowds at most places, and a few backpackers on the grounds of the main temple would be smoking funny cigarettes. Going to Banteay Srey required an armed escort.

The Khmer Rouge even briefly held the area in an uprising later in the year, back in the days when they were still operating.

Am glad I got to see Angkor before it was overrun, though. Saw it again in 2000 and crowds were noticeably heavier, though probably nothing like they are now.