will the compaq presario sr1625nx with the express 200 video card work for microsoft flight simulator X? or will an upgrade to radeon hd 5670 card work better? and is the newer card compatible with that compaq computer?
That's an old, slow, out-dated computer. But, yes, even the HD 5670 will be a great improvement on the old integrated graphics. It may even make you think you have a new computer ;-)
... assuming you have enough RAM. If the system has the original 1GB memory, you need more.