Installing Parellels 5.0 ipo v4.0

I purchased a boxed upgrade for Parallels 5.0. Upon installation a message states it will require Version 4.0 to be un-installed before installing version 5.0. The message asks "OK?". NO OTHER EXPLANATION.
Can I safely do this if I have been using v4 for 2 years, Is there data or settings that need to be carried over to the new version???? Of course I cannot get tech support from any of your operations because I have not yet installed the program and I am not about to spend money on phone support for a brand new product already purchased. Come on guys!!! Give us access.