iMac freezes on startup

Ive had a Samsung 830 SSD installed in the optical drive area of my 27" iMac. It has been working fine up until the last month or so. Lately, the screen freezes up a little while after I log into my account, or as soon as I log in. It also happened when I logged into the original HD in my iMac. The only time it doesnt freeze up is when I log in as a guest. Ive been on it via guest for an hour now, and its running normally. I just recently got the iMac back from service, in which the screen and graphics card was replaced. When I received it, I removed the optical drive, and re-installed the SSD. Would the SSD be corrupt, and should I re-install ML onto it? I just find it weird that it freezes up after a bit on my account, but runs normally when logged in as a guest. Thoughts?

Mike in Kansas said:

Could be something that runs in the background when you start that account versus the guest account. I have quite a few programs and apps that automatically load when booting up. At one point, one of them no longer played nice with the OS - I think when I went from SL to Lion. The computer would hang on boot, until it finally decided to skip trying to launch that program.

Look in your System Preferences > Users and Group > Login Items to see if anything in there could be causing problems. You can remove them temporarily to see if it helps.

Click to expand...

I dont have much in terms of Login items. I use to use istat pro, but even that I took out after a while. Here is pretty much what has happened:

-It freezes up a few minutes after logging into my account (which is the SSD)

-I switch to the original HD in my iMac, and log into that account, which is still running Lion, and that freezes up after a few minutes.

-I log in as a guest, and created a new admin user. I started to run carbon copy cloner, so I can copy the original HD so I can add a new WD 2tb drive, and that newly created admin user freezes.

-I once again log in as a guest, and EVERYTHING is working fine. WTF?!?!?! Im running the copy, Im surfing safari, listening to the radio in itunes, and playing cards on full tilt. I dont understand why everything is running fine as a guest, but I cant seem to get anything to work otherwise. I have the guest account set to sharing btw. I really dont know what to do.