Firstly your video card is NOT going play a major factor in your video editing, unless you have some crap 1MB card from 6 -7 years back.
ANY new video card out there will work basically the same when it comes to video editing, same goes for sound cards.
If you want something really cheap a Nvidia Geforce 2 Mx can be had for around $35 and a Sound Blaster Live Value can be had for around $50. Both are decent cards, both would work well for video/audio editing.
Now if you want to play 3D games that's another story. You'd probably want a Geforce3 or Radeon 8500.
that computergate.com place looks like a ripoff.
Check out newegg.com
I'd grab the Sound Blaster Live 5.1 OEM for $32
http://www.newegg.com/app/ViewProduct.a ... 137&DEPA=1
and then get the Chaintech Geforce3 card for $105 or the 128MB verison for $125
http://www.newegg.com/app/ViewProduct.a ... 487&DEPA=1
That'll get you ALOT
farther then that computergate place and I've ordered over $1,000 worth of parts from NewEgg with no problems, so they won't rip your off.