based on the title of the thread he is asking for two opinions, the best videocard and the cheapest videocard, otherwise the title should have been the best cheapest videocard if that he is looking for.

nanghihinayang lang ako sa "legal" copies ng games na mga bibilin mo tapos sa entry level na videocard mo lalaruin. kahit legal yan di mo naman ma-eexperience ang full beauty ng game mo.

for the games that you have mentioned i would not go lower than a 8600 series nvidia card. and i suggest go and upgrade your ram. it should be atleast 2gb (but 1gb should suffice).

heres my desktop spec.
AMD opteron 146 OC * 3ghz on a lanparty ultra-d mobo
1gb ddr400 ram, dual channel
msi 7800gtx 256mb videocard
SATA2 disk drives
XP SP2 OS

with that setup i can run cod4 with all settings high.
the framerate is quite acceptable at 35-40fps * 1280x1024 reso. and may lag parin yan on intense battles.

if you plan to play those games i'd suggest you invest on a good midrange videocard and not the "best cheapest" you can get, otherwise sayang lang yung mga "legal" copy na games mo.