Here is my observation of the beaches and some good places to stay.

Victory Beach is over two kilometers long and narrow. This is the favorite of the backpackers with cheap guest houses on the hill above. There are a couple of good hotels, the Holiday Palace which has an excellent Thai restaurant and nice casino. Also the fairly new Peak Hotel. The beach itself is in my opinion is the least attractive of them all.

Independence Beach is fairly long but the sandy area is quite narrow, making it best when the tide is low. Overlooking this is at the northern end is the newly renovated Independence Hotel said to be opening late 2007. This hotel is not cheap ($100+range) and has a pool. Also the more modest Sea Breeze and New Beach hotels are here.
Sokha Beach is probably the best beach and that is where the 4 star Sokha Beach Resort is. It covers the most of the beach and is for hotel guests only. No *beggars and touts here. Nice Pool

Ochheuteal Beach (known as Serendipity Beach at the northern end) is long and narrow and very developed with many restaurants and bars. It appeals to visitors seeking middle to upper range facilities on the beach but there are also budget guesthouse and bungalows right on the beach. It is a very popular and busy spot. Here you will find the upper mid range Seaside, Crystal and Golden Sand (pool) hotels and the less costly but good Holiday and Jasmine hotels .

Otres Beach is a really lovely beach with hardly any people but you need transportation to get here. There are no hotels and this is a perfect spot to get away from the crowds and be by yourself for awhile. Just make sure that you arrange for a moto back from here.

Hope this helps