Hi using something like the PicoLog 1000 as I said before you would have to ensure your device is connected to your PC at all times.
Providing you configure your settings accordingly logging for a week is achievable.
The most reliable way is to use a remote data logger, like the EnviroMon, At the heart of the system is the EL005 logger, which has a micro controller and can sore up to 250,000 samples. The EL005 uses a serial port to configure it on the computer and requires a 12V power supply which comes supplied with the unit. The logger is initially programmed on the PC and then can be left to run independent of the PC or remain connected to the PC. To view the data the logger would then be connected to the PC and it will then download the data when the software is running (software comes free).http://www.picotech.com/e_loggers.html
To get your measurements from the sensors we have a range of sensors which can connect to the logger. These convert an analogue signal from a sensor or input into a digital reading which is stored by the logger. Up to 10 converters can be connected to one logger. We have a range of converters for different applications.http://www.picotech.com/e_converters.html