Extremely slow Windows Welcome screen, please help

I recently found myself in a financial rut and decided it would be a smart idea to pawn my laptop for some quick cash until I received my paycheck the following week. Well, I went through with the pawn, then the following week I went back to the pawn shop to pick up my laptop. Everything seemed to be fine, no scratches or noticeable damage was done during its little vacation.

I returned home and plugged up the laptop, I turned it on and came back awhile later and entered my log-in information, then left awhile longer. When I came back and tried to check my e-mail, I noticed an extreme slowness on my laptop. I tried to restart the computer through Windows, but after 10 minutes, the computer was still on the "Logging off..." screen, so I held the button down and shut down the computer, when I rebooted the computer, it got stuck on the log-in screen, I could not enter a password.

I then did another manual shut down and went straight for a system restore, but for some odd reason, my restore points had all been deleted before that day, there were only 3 available, and they were listed as system updates, so I went ahead with the earliest one.

After the restore, my computer was still lagging horribly. I installed AVG 2015 freeware and ran the usual antivirus procedure along with a PC tune up. So, now, after I log in, my laptop appears to be processing at pre-pawn shop speeds. Yet, I'm left with the problem of my log in screen. I turned it on tonight and it was stuck at the log in screen and would not let me press enter after I had entered my password. So, I did another manual shut down, rebooted, and tried my log in again.

I clicked on my username, entered the password, and hit enter. I didn't time it, but it took at least 20 minutes after I pressed enter on my keyboard to load my Windows Explorer. It was stuck on the screen that says "Welcome" with a blue and cyan loading circle to the right of it. All of the specs in my profile are current and up-to-date with the laptop that is having problems.

HP Pavilion dv6, Windows 7, 1.5GHz Quadcore, 6GB RAM
Please help!

Hello jmad and welcome to Seven Forums.

I'll bet the folks and the pawn shop had a good time playing with your laptop. Wouldn't be surprised if they managed to get some malware installed or messed up some system files.

One of the Forum experts prepared a couple of tutorials that might help you diagnose what your problem/s is/are.

Troubleshooting Windows 7 Failure to Boot

Troubleshooting Steps for Windows 7

And this tutorial has some general suggestions on how to optimize Windows 7.

Optimize Windows 7

Thank you very much for the quick reply, your help is greatly appreciated.
I began with the first step, and this was the result:

Start-Up Test; Short DST Failed
Failure ID: MC3SW2-61779W-QFPK01-60R703
Product ID: A6Y57UA#ABA

Run-In Test; Short DST Failed
Failure ID: MC3SW2-61779W-QFPK01-60R703
Product ID: A6Y57UA#ABA

System Tune Up
Failure ID: MC3SW2-61779W-QFPK01-60R703
Product ID: A6Y57UA#ABA

I will be continuing with following of the steps, although, I figured I would post this in hopes that it may help resolve the issue. Thank you for your feedback

The short DST failure could be an indication that the hard drive is failing.

Hard disk Short DST test failed - HP Support Forum - 3008857

If you have any important data on the hard drive you might want to back it up. Then continue with the additional troubleshooting steps. In the event you have to replace the hard drive, this tutorial should help.

Clean Reinstall - Factory OEM Windows 7