I've never played the DC version. so i dont really know.
they both should be pretty much the same. but since the ps2 version came out after the DC version, i'm guessing it has just a few minor improvements.
btw, TXR2(DC) is the second title. i dont think its the same as TXRZ(ps2), which was a port of tokyo highway battle(also known as TXRZ).
I think they kinda got people confused with all the Tokyo highway/extreme racer game names.
which one exactly are you talking about? i'm getting confused now too.
neways, there is a game called wangun midnight coming out for the ps2. its looks pretty much the same as TXRZ but with better graphics and with characters.