Multiple sensor sending data to a PC through serial port...

What you describe is one of the best and most common uses for Arduino. I assume you haven't actually tried it yet, but it's just a matter of reading the various sensors in turn, printing the result, and the going round again. I'm an Excel fan. Below is a link to using PLX-DAQ. It is a freebie macro for Excel that makes it a terminal. Most of the work for this is in Excel, the Arduino bit is easy .

http://homepages.ihug.com.au/~npyner/Arduino/GUIDE_2PLX.pdf