I suggest G.Skill for ram. G.skill is the best in terms of Price/performance today and no one can argue this either. Get any model of G.Skill DDR2-800 and you will be fine. However the G.Skill NR, HK, and HZ model are just awesome.
For a motherboard the P5B Deluxe is a good board but the P5B-E has just about the same features, overclocks better, and is actually cheaper.
Western Digital are good but still today Seagate's 7200.10 drives are just awesome and more reliable.
That monitor is expensive and honestly I prefer the Acer Office line for around $280 as it's a great monitor and saves money; however Samsung make some of the best monitors and in no way is that a bad a choice.