Laptop Running Slow, Will Not Boot In Safe Mode?

I happened to run across this forum while searching for answers to my computer troubles through Google.Here's the issue, my laptop is no more then a year old.  It's a Dell Model N5040 running Windows 7 Home Premium, Service Pack 1.  For the past week or so my computer has been running increasingly slower, and i cannot for the life of me figure out why.I am only using 36gb of a 446gb hard drive, I have 4gb of ram and have run a virus scan, disk cleanup, and a disk defrag..  It does not run slower while doing certain things infact it seems to selectively slow down.  I attempted to complete a disk check of my C drive.  This has found a few bad sectors which have been either removed during the check or manually however after a week of attempting to run the disk check I have yet to fully complete a single check.  It will freeze at some point on every step and never recover.

I use Trend Micro Titanium as my virus protector and I have even attempted to use their house call software to check if maybe my virus softare was compromised   I have used Spybot search and destroy and CCleaner in an attempt to clear up any clutter and/or spy/malware.  My only conclusion is that maybe some Windows driver was deleted by mistake through CCleaner.  I have attempted to start my computer in safe mode however even this cannot be completed, it freezes and never recovers.Nevertheless, I am at an impass i am unsure on where I go from here and would obviously prefer to fix this myself rather then let some self proclaimed "tech" at a shady I.T. company tell me i need a new computer because they cant figure it out either.