So I am basically out of space on my 160gb hard drive in my PS3, forcing me to delete a few games that I didn't like much even though I want to give them a second chance. I already have like a 250gb hd which was in my old fat PS3 till it got the YLOD and that's why I have a slim now but I really need some space. So, can I upload all of my saves to the PS Plus cloud and back them up to my new hard drive? Has anyone does this? Any and all help is appreciated. I'm getting two new games in a few days and I only have 10 gbs left.

Yes you can,
I have moved saves from my ps3 to the ps3 I gave to my brother, after putting my account onto the ps3 as well

Now if all you want to do is put them on the cloud to then put them on a new HD I'm sure that would work as well.

Yeah and it was already reformatted previously when my fat was still working but my real question is once I swap hard drives how do I get my saves into my actual hard drive? I've tried before and I don't know if you can move them from the cloud to the hd. I mean I have PS Plus for a year but long term wise I need my saves on my hard drive :/

Any help?

your 250GB will be formatted again once it's in your slim unfortunately, anything on that will be lost.
after your saves are in the PSN+ cloud though you can get them onto your "new" HDD as long as the primary user account on the PS3 is linked to your PSN+ account where your saves are. it's then just a case of sucking your saves back from the cloud to your PS3. the software versions of the games in most cases will have to match with your saves so you'll probably have to patch your games back up to date for the saves to work and sometimes trophies too.
That's the way I understand (and have used) this

note that some games will allow you to export your games to another attached drive, but some games will not allow you to do this.

AFAIK, all games saves can be backed up to the cloud and restored from there (need verification) with PSN+

my friend did just this and it worked well enough. As spankey said, make sure you are up to date on patches, my friend lost his save on one game because of version issues. Also, remember there is a 24 hour wait from when you upload to when you are allowed to download.