I have very similar problem
After almost two years having this phone working properly, I decided to move to clean version of ICS (without any local carrier garbage). I used official update guide with flash tool and rooted my phone. No boot unlocking performed. Everything was working properly for about month or two, but after that some lags with screen started.
Many times the phone’s display remains off after unlocking. I feel that phone is working, there is vibrating while unlocking and sounds of clicks and there is light under navigating buttons. So I’m locking phone again with power button and try to unlock again. That might succeed after one or two attempts like this, and might take longer. After the display turns on successfully, phone is acting as usual.
I tried “Update Service” but it tells me that I have latest software. Flashing back to GB or reflash it again to ICS does not help.
For now I’m leaving phones display active while charging and that helps me to have it available.
I doubt that it is worth to give to service repairs because it will cost too much. My question: is it a LCD that makes the problem? I’m thinking just by a new LCD and replace it, will it help?
Any help will be appritiated
