Windows 7 freezes on start up logo

Solution
If you can boot* and be stable for awhile..
Download CCleaner and run the Clean and Registry portions both. It may be registry errors or software conflicts.
https://www.piriform.com/CCLEANER
If CC finds a ton of stuff, you may want to re-run it again. It sometimes finds more.

*If you can't boot normally, see if you can boot to Safe Mode with Networking. (tap F8 at boot up)