NAS/HTPC with different drive sizes

[Kasboh]

Hi, I want to build the NAS/HTPC server. I have no previous experience in it, so I need a couple of advices. Please excuse if I ask stupid questions.

1) First of all I want to have a system with redundancy and be able to use HDD sizes of different sizes. Also it should be possible to expand the storage with extra drives, without losing any information.
Is this possible at all? What software should I use?
Should it be hardware RAID or software?

2) Main goal is to build NAS server. But is it possible to do streaming (HTPC) from it? What software (OS) should I use?

I’m open to any suggestions.

Thanks

 

[Hydaral]

There are already a number of threads here about using multiple different sized disks, see here for example:

http://forums.smallnetbuilder.com/showthread.php?t=4114

 

[Kasboh]

Thanks for reply.
After some reading I'm tending to install windows server 2008 R2 (because I have msdn license for it).
For the different sizes HDD I think Drive Bender will be the solution.
As I'm going to buy Zotac NM10-DTX Wifi mobo, I'm not sure I will get good driver support from Unix systems and won't be able to use it as HTPC.

What I'm not sure, is how to built in redundancy in this system. Is Drive Bender good enough for this?