You don't need a 'special' mat. However, it does need to have anything other than a plain monocolour pattern. In other words, if it is, say, all one colour your mouse won't work - it needs changes in colour or pattern. So if you have a mat that has a picture of your fav aircraft, or the kids, advertising, etc, you should be ok. Don't be taken it by salesmen trying to sell you 'special' optical mousemats at exhorbitant prices. In fact, you don't need a mat at all - a computer desk with something like a wood pattern will do!
I'm not sure about the mouse going to sleep - that may actually be a design feature to save power - check you mouse settings in control panel...