Yes it will, though I have a Radeon 9800 Pro (the 9700 isn't made any more) and I am getting about 25-140fps in Half Life 2 at 1024x768high quality (0x antialising, 4x antistropic) in water levels (140 max for inside) (doesn't even get any better at 640x480) and I have a pretty good system (check specs below)
Though it will run new games, if you want high settings, its a no no.
A Geforce 6600GT is a best buy for gasmes to last a long time for the mo, and only costs around 130-160 quid ( i wish i waited and got this than my Radeon 9800 pro which i paid the same price for, but a long while ago)
Hope this helps