A while ago I switched from Virtual Server 2005 R2 to VMware Server and so far I think it was a good switch. Unfortunately it wasn't without some consequences -- mainly that I should have read the procedure prior to converting my VM image. I had the Virtual Server extensions installed on my image and I forgot to remove them and then I seemed to be unable to remove them without doing extensive damage to the image. Now I am not able to install the VMware Tools as it causes the mouse to freak out and navigating through the keyboard is increasingly challenging these days, not to mention a pain.
I even went through the trouble of searching through the registry to find the Microsoft extensions and remove them. I also removed the C:\Program Files\Virtual Machine Additions folder and used Autoruns to remove the additions driver. The bottom line is -- don't bother -- it broke and wasn't worth fixing. Alas, I will have to put up with the annoyances (having to use Ctrl-Alt to release the cursor, finding out the system time is inaccurate after suspending the image, not being able to use the clipboard across the host and VM, etc.).
Since then I created a new image from scratch (for a different purpose so I still occasionally use the older image) and it is working great. Oh well, I'll get around to recreating the old image sometime soon.