buying a pc very shortly: are these spec good to run crysis on highest?

[Soleron]

No, the GTS 250 isn't enough for decent settings and resolutions. I'd recommend at least an HD4870 1GB or GTX260, both of which are similar performing.

Or if your budget can take it, an HD4890 or GTX275. Anything above that is a ripoff and won't give much more performance but will cost a lot more.