viedo cards

I need to replace a couple of video cards.
What cards are considered pretty dececent and what is the price range?.
Useable in both the LInux world,specifically Mandrake 8 , and also by M$
boxes.
And also, are there any good reasonably priced flat screen monitors? If not,
what would be a decent quality Monitor run?

I likely would look around at Fry's Electronics but somewhere else would be
fine also.
I would appreciate advice on updating this stuff.

Roger