new gfx card compatibility

i want to get a new graphics card.
http://www.bjorn3d.com/Material/Images/383_bfg5950-1.jpg
this is my old on. i dont know what type of connector it is, ive been going through the internet and i think its called pci but i have no clue really. what kind of new card do i need so it will fit?

and if you feel like it you can find me a shiney new top of the line one thats compatible. please and thank you.

 

http://www.thgtr.com/motherboard/20030707/images/asus_board_big.jpg
and this is my mobo, the large brown slot is where the gfx card sits now.

 

:confused Your first link comes up with a "direct links not allowed" error, and the second link just produces a "Toms Hardware" logo...

Perhaps some functional links, part numbers, makes/models, etc, would be more helpful

(anyway- if you have a large brown slot like the one in the picture below, then you have an AGP video card which is more-or-less an obsolete format )
http://www.hardwarezone.com/img/data/articles/2004/1083/agp_slot.jpg

 

http://tinypic.com/view.php?pic=21damd&s=4 card
http://tinypic.com/view.php?pic=jqkpqp&s=4 mobo

sorry for before

 

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2412161&CatId=2234
would this be a good replacement if i want the best i card i can get that will still work with my mobo?

how long should i expect this card to last me in terms of needing an upgrade to play the newest games?

would it be better to build a new rig with more up to date stuff now?