Since the beginning of 2010 I've been experimenting with running inside on my Windows laptop. I always tried to stay up-to-date with the latest stable releases. In the beginning it worked like a charm but lately there have been some issues. It seems that has not been able to keep up with changes in the latest release, 10.10. Problems with the guest freezing due to using several cores arouse already during system upgrade from 10.04. It seems to be working fine when using only one core, but who wants to go slower just because of that. Lately there also seems to be some problem with the guest-additions leading to a painfully low screen resolution of 600x480 in the guest OS. It's just not working these days....
So, what is the alternative? Since remembering everything working fine during the spring I decided to roll-back to earlier versions. Now I'm running 3.1.8 with 10.04 LTS (both desktop and server) and it all works fine. From now on I will be much more reluctant to upgrade to new releases, and definitely be sure to create a snapshot of the virtual machine before any upgrades.
All in all, the combination
and works fine, but for a stable working environment be sure to stay off the bleeding edge!