I`m trying to figure out if this is a software problem or a system problem. I recently got FSX and when i go to land or takeoff the game starts to stutter really bad.  I`ve played around with the settings( had everything ultra low ) and it would still do it.  I could have everything high and just sitting there, no problems.  Once the wheels are off the ground,no problems.  Its just taking off that it stutters.
My system is a Dell Vostro 200 2.6ghz Core 2 duo, 3gb memory and a Visiontek 4550 pcie video card.

Other possible causes...

Sound-the extra sound processing associated with take-off. More noticeable with m/b integrated sound processors. Try turning sound off (Q toggles sound).

Spray effects-If you're on runway conditions (rain/snow/dirt) that produce wheel spray, prop or jet wash. Try turning the 'Special effects detail' slider down, or try it on a summer, dry, paved runway.

Dave