your request is kind of vague from a computer repair tech and builder point of view, if your looking for an off the shelf, get a dell with a 3 year extended warranty and then when you reach 2 years 11 months, pull the hard drive and smash it on the ground, wait 5 days for the tech to bring you a new PC,
if you are looking for something with long shelf life and room to grow then you cannot find this in a name brand, go custom built, with the dual monitors I would guess you want something with decent graphics engines so go dual SLI "Nvidia"
to get some good ideas I recommend tigerdirect and check out their barebones, its decent quality and you leave yourself open to many options down the road.
Good luck and if I can be of further assistance please ask away.