NI makes some DAQ cards that can scan data at 10 MHz on each of 4 channels, a 2 channel digitizer that can sample at 15 Mhz and several other products that can sample in 100s of kHz to 1 MHz range. LabVIEW is certainly capible of doing what you describe.
Do you currently have an applicaiton you are having problems with? If so, can you provide some more details like what DAQ device are you using, what version of LabVIEW, what problems are you having....
Ed

Ed Dickens - Certified LabVIEW Architect
Lockheed Martin Space
Using the Abort button to stop your VI is like using a tree to stop your car. It works, but there may be consequences.