I have an NEC 2500 something or other DVD writer drive in my PC.... Uptill now I have only needed to use single layer, 4.7gb discs, but wanna try a dual layer disc (8.5gb)

Stupid Question : do you need a dual layer specific drive to write to these discs or will a "normal" drive do it?

Lastly, where's good to get DL discs from, without spending bucks (I usually get single layer DVD-R's from Tesco for about £5 (20pack I think)

Thanking you please