ADC10 and DTC (MSP430 F2xx) - problems in reading analog input on multiple channels
... you could start by using the ADC10 interrupt vector instead of the timer0 interrupt vector ... it also looks like you're going into LPM0 at startup then switching to LPM3 after the first interrupt wakes you up (just reading comments here) ...

See section 22.2.10 of the manual, excerpted here for convenience.


  One interrupt and one interrupt vector
  are associated with the ADC10 as shown
  in Figure 22-16. When the DTC is not
  used (ADC10DTC1 = 0) ADC10IFG is set
  when conversion results are loaded
  into ADC10MEM. When DTC is used
  (ADC10DTC1 > 0) ADC10IFG is set when a
  block transfer completes and the
  internal transfer counter 'n' = 0. If
  both the ADC10IE and the GIE bits are
  set, then the ADC10IFG flag generates
  an interrupt request. The ADC10IFG
  flag is automatically reset when the
  interrupt request is serviced or may
  be reset by software


I would also consider perusing the TI-provided code examples for your particular chip variant.