partition error [there is not enough space available ] please help!

so, i have been trying to partition my c drive for almost five days now with not luck.
first thing i tried was my computer-right click-manage-disk manager...i tried to partition from there only to find i only had 75mb available for partitioning (when i actually have almost 30 gigs unused, in theory anyways!), so i googled that and tried all the work arounds possible...i.e disabling system restore, paging file, difrag ( windows' and several other 3rd parties')..that did free up some space, about 7 gigs! oh well, i thought i'd partition that much at least but NO, now i'm getting a "there is not enough space available on the disk" error message!
i have already tried third party partitioning programs such as easeus, partitioning wizard, etc..but like i said, no luck. they seem to the job but as soon as it asks me for a reboot the computer just crashes and im back to the beginning. this is so annoying!
any help will be greatly appreciated! thanks (:

You could make your Recovery Disks so you could delete and recover that 10gb into C using free Partition Wizard bootable CD. You can even delete the OEM partition if you dont' use any of the useless factory utilities that park there whose links are broken if you clean installed anyway.

Back up your files, Make the Recovery disks as shown in Manual (located at Support Downloads webpage for your model computer), test that they boot and cue up to see what options they give.

Boot PW CD, rightclick Recovery>Delete, OK. Then Delete OEM if you want. Then rightclick C>Resize, slide left grey border all the way to left, OK. Apply.

If Win7 won't start now, boot the Win7 DVD Repair console or Repair CD, click through to Recovery tools list to run Startup Repair up to 3 separate times with reboots to repair the MBR.