I have a video of takeoff roll (infact, I have 3 complete flights recorded) in a B737-300, in December of 1994. The temperature outside was about -5 degrees celzius, and I measured the time needed for aircraft to reach 80 KTS, V1-Vr (a/c was half-loaded with passengers):
80 KTS - 15 seconds
V1 - 27 seconds
Vr - 27-28 seconds (almost instantly after V1 call)
I don't know the exact t/o speed (Vr), I think speed was 134 KTS - it was long time ago (1994) and we shoot from hand and camera was rocking like hell so we couldn't zoom sharp on the airspeed indicator. V2 speed, as I recall, was 143.
I think that the time needed to reach 80 KTS will give you some information about 737 acceleration
But, that depends of temperature, wind, runway condition takeoff weight etc...