Quick newbie question!

From the research I did when I started my site about a month ago, a Windows server would be your best bet. It usually has more flexibility when it comes to server side scripting. You can use tools like asp.net, MySQL, or SQL Server databases. I've also noticed that the Windows servers tend to come with a lot more software add-ons like blogs, forums, etc. Hope this helps and good luck!

Linux is stronger and more secure IMO.
The reason for the price difference is windows server you have to pay for while linux is freeware.
The next version of windows server (longhorn - the operating system is vista) you may end up paying for the updates - is still in beta due for release end of this year or early next. With anything microsoft you will be forevering updating security holes, linux has some sure but not nearly as frequent.

There is more software/addons that run under linux - blogs, forums, auctions, feeds, stats, email, etc which are mostly free (see places like hotscripts.com) where as finding free asp scripts aren't as easy.

At the end of the day both linux and windows can sort of do the same things, most comes down to personal preference if cost isn't a factor.

You didn't say where the information was being sent as in precautions, are you just sending text emails to the webmaster or html emails, or just putting the information in a database? Things like credit card details should never be sent via email.

As far as reliability and security is concerned, I'll prefer Linux. If you talk about the webmaster front, a good Linux Web host should always be a good choice. No matter if you are running a simple Website or a big, professional Website, Linux is always a good choice IF you don't need .NET & MS SQL features.

Tools that comes with a good Linux Web hosting plan like cPanel, Fantastico, etc.. will make your Webmaster life a lot easier .

Excellent information. Thanks for your help folks!

Busy, I am just sending text based emails from the site.

Cheers