Re: hard drive
A brand new 320gb or even a 500gb could well be a possibility within the range you’ve mentioned. However, try and purchase a drive thats higher on the RPM scale, 7200rpm hard drive instead of the 5400rpm drives scattered around.
If I were you and if the drive was going to be used primarily as a system drive, I’d get the 320gb 7.2K drive over the 500gb 5.4k drive any given day. The increase in disc platter speeds helps substantially in getting your desired applications/Operating systems loaded up in minimal amounts of time.
If its going to be used as storage, I’d opt for the 500gb if I wasn’t going to be copying stuff over frequently and instead relied on getting my stuff from ftp servers, torrents etc.