I've been experiencing this issue since I updated to VMWare Player 5.0.
Whenever I start a virtual machine, my CPU gets loaded to 100% (only 2 of 4 cores are for the VM) for 2-5 seconds, sound (mainboard) and mouse struggle with the lag spike (according to my mouse I have ca 0.5FPS on the desktop). After that the load disappears and everything's fine.
I tried that with following VMs: Windows XP, Ubuntu, Android. All of them have this.
Here is the log from my latest Ubuntu startup: http://pastebin.com/RnxtG2id (take a look at line 1077, it's exactly the time point the load spike starts)
Thank you in advance.