Hi Annii,
We actually started off Mid 2004, although onesmarthost is still a relative new company we do currently host 145 websites, our aim is to provide the best hosting service possible and to help customers as much as possible each new customer also receives my personal mobile telephone number for emergency support.
If I was to be run over by a bus I have legal documents in place which will hand over all access to the servers to a long trusted friend who currently works for a blue chip company providing server support so for our customers the service will carry on as normal, in case of the worst i.e death the business "Smart PC solutions Limited" will be signed over to my partner and my good friend will take over the server operations.
Regarding Windows and IIS, PHP works exactly the same, somethings such as PHP Gallery
http://gallery.menalto.com/ is an example of something which does not work straight out of the box with Windows due to its need to access windows cmd.exe, but we can help customers to get it working within a few minutes by applying the relevant security permissions for that domain.
.htaccess is another component which is not available in IIS but we run on all our servers an IIS ISAPI Filter
http://www.isapirewrite.com/ which handles SE Friendly Urls which our website is running at the moment again we can help customers get the right rewrite rules for their sites.
We also run the best mail software and stats software on our servers
http://www.smartertools.com - smartermail and smarterstats
Thanks