i spent around a month in Cambodia. wouldnt recommend booking a tour here as there are plenty of options available once you get there and A) they will be much cheaper and, B) the money you are willing to cough up will be going into the pockets of the people rather than some tour operator.
If i was to go on a couple of weeks holiday i’d consider something like this:
Fly in to Bangkok & have a couple of days there.
Next head to Siam Reap. There’s a few ways to get there; organised bus/coach, private taxi to and from the boarder, fly. depends how much you have to spend. air asia will probably fly BKK to Siam Reap. Be aware that if you do take the organised bus/coach option the road on the Thai side differs drastically to the one on the Cambodian. Think dusty, bumpy, sweaty and very long. A great experience when i was backpacking but probably not for a relaxing holiday!
At least 3 days in Siam Reap. There’s loads of good quality, modern and cheap guest houses available, reckon you might even find one with pool/spa facilities! You can arrange for a guide with an auto rickshaw to take you around Angkor for a 3 days and he’ll know all the good spots and generally be useful and informative. Some great memories from there, watching sunrise & set is ace – if you haven’t been before you’ll love it! Not much else to do around Siam Reap though…
A couple of days in Phnom Pehn. A bit grim, most of the toursim is based around the auto-genecide, but i think it’s worth a look to get a proper understanding of the country and definately a good idea to put some more money into their economy. If you wanna shoot a gun – do so here. I wasted $20 in about 5 seconds firing off an M60!!!
Head down to Sihanoukville as gonefishin mentioned. But i disagree that you wont find it relaxing. underdeveloped is good in my book. didnt get too much hassle from people trying to sell us stuff, good clean beach etc. There weren’t any big modern hotels when i was there (3 years ago) so you might not find the spa/pool thing but i’m sure muching fresh crayfish on a sunlounger will make up for it 🙂
Would probably head over the boarder to Ho Chi Minh City for a few days at the end of your trip as it’s easier to fly back to Bangkok from there and is a great city to explore!
Hope this helps! I had a great time in Cambodia – the people i met were all great, apart one lass who swore she wasnt a hooker and then threatened me with a bottle the following day. but that’s a story for the grandkids 🙄