I an not good with this computer tech stuff. I need more room on my comp. what can I buy or add?More ram or more room on the hd?Assuming you believe you are running low on hard drive space the options are many.
1.REMOVE permanently any unneeded files/data/programs.
2.Transfer to alternative media; files/data (photos for example) to portable alternative storage devices. IE: flash drives/CD disk/DVD disk THINGS you want to retain but don't need for your computer to run properly.
3.Replace your current hard drive with one of greater capacity. If this route is chosen it will entail a lot of preliminary work 1st.
4.Purchase an EXTERNAL USB connectible hard drive to be an adjunct to the primary internal one in the laptop.
5.Store data/photos on an external site that provides this service
  There are probably even more ways to do what you want but this should go a long way to achieving your goal.
truenorthI like to use ccleaner to remove my temp files (which at one point in time, was 13 gigs lol) and treesize will give a good indication of what's EATING up all of the space.

Assuming the HDD in question isn't your D: recovery partition on your windows vista partition that's nagging at you that you're running out of space because you set your backup to go there, I would have to recommend a new larger hard drive.Hi,
I suggest you to remove the unwanted things. Use any good PC cleaner tool to remove all temp files, histories, cookies etc. More over do disk defragmenter to remove the space created during cut-paste OPERATION. You can even compress files using compression tools to have more things. If this is not enough my advise is to replace your lapi hard disk (HD) with high capacity HD.   Who's feeding the parrots today?    truenorth