Free up disk space in vista??

Hello all, I was wondering if anyone knows how to free up disk space in vista . I supposably have a 320 gb harddrive installed but when I go to my computer it says under Acer (C) 214gbs free of 288gbs . Then when I go to defrag it says: Select all disks , Acer C, or PQSERVICE. there are those three choices when you go to defragment the harddrive. The computer is an Acer Aspire, which came with no recovery disks. Luckily though I get to upgrade to windows 7 when it comes out, Acer is going to send the disks. I do not know whats up with this harddrive though, maybe too many restore points?
Any help appreciated.

If your system didn't come with restore discs, then there is a recovery partition. You can create restore discs from that. The recovery media creator would have been one of the first screens that popped up when you first booted the computer.

"214gbs free of 288gbs" , means you have 214 gb free space.

PQSERVICE is Acers version of a hidden recovery partition. Newer pc's usually have a recovery partition or allow you to create a set of recovery CD/DVD's , as MK noted. Check your manual.

"Select C" to defrag the main partition where Vista is installed. PQSERVICE does not require defragging.

You can open My Computer > right click C: drive > select Properties .. to view the drive properties and confirm free space.

The 320GB sized hard drive is before partitioning and formatting. You get 288GB after all that is complete and Windows is loaded.