@Cyberus
I prefer Seagate Barracuda series myself. I've got total 1,120 TB of Barracudas and not a single problem. For 300GB it would be ST3300831A and ST3300622A. ST3300622A is newer so it has slightly better specs, but ST3300831A is fine aswell. These drives are whisper quiet and have 5 year warranty.
However, if you look into some other manufacturer drives, avoid Maxtor and IBM/Hitachi at any cost.