Oh... this is dangerous stuff. I would not recommend running EPiServer 4 on anything else that Windows 2003 servers.

I have managed to get EPiServer 4.62B sites to run in development environments on IIS 7 in compability mode with some tweaking but it is not something I would dare to use in production without more extensive testing. I think I got it to work rater fine but there was some issues with the online help and a few broken images in edit mode if I remember correctly. 

It is probably easier to use a more modern database server runing the database in compatibility mode. That usually works well since EPiServer tables, views and stored procedures are rater straight forward.

Thx Fredrik... Our plan is not to change OS, we know that it is, like you say, dangerous stuff.

But running a SQL 2012 in compatibility mode instead of an old 2005 would be nice. And as you say, the Episerver database is very "simple" and don't use an spcial features.