Trouble with Macbook display -- brightness cuts out or gets wavy if I move the screen around Macbook Pro, 2008, 15 inch Running Mavericks 10.9.2

If I move the screen around at all while it's running the brightness will almost always reset to as if it was zero or it gets these wavy interference pattern-like regions of bright and dim. (Image similar to my situation: http://www.lavproductions.com/images/macbookpro_screen.jpg)

Now I'd say this was a hardware issue, but once it does this, I can just put the display to sleep and then it's always fine after that. The screen is back to normal. I don't move anything at all. If it was a loose connector then putting the display to sleep would presumably not help.

Here are some other sites describing the same issue:
http://www.geekinheels.com/2008/05/02/apple-replaced-my-macbook-pro-for-free.html
https://discussions.apple.com/thread/1633312
https://discussions.apple.com/thread/1627678?threadID=1627678&amp;tstart=0

But they're fairly old and I have been going through them and I don't see anything definitive. Some say it's a bad connection, but then why would putting the screen to sleep fix it?

Possibly related, but probably not, is sometimes the trackpad cuts out completely, and other times the keyboard cuts out as well. Putting the computer completely to sleep usually fix the former, but not the latter, so when the keyboard cuts out it would 
And for long periods of time I won't have any problems. Went nearly a month without either the trackpad or the keyboard locking up. I can't say for sure, but I think it only started after Mavericks, and I don't think the firmware updates to fix the issues people were complaining about covered my model.

I realize it's an old Mac, but I'm very confused by these problems as they seem to be both hardware and software related...

Thanks for your help!
As a former Apple technician in a retail store, I can tell you that if an SMC reset didn't fix the "stage lighting" display issue, we replaced the display assembly.  Probably not possible through Apple anymore since a 2008 MacBook Pro would be considered vintage...

For the keyboard/trackpad issue, you might try reseating the flex cables underneath the top case.  iFixit.com has great guides for opening up your Mac. You open your computer at your own risk. :)  If that doesn't change anything, could be a bad top case.  The keyboard assembly and top case are separate on the 2008, non-unibody MacBook Pro, so then it's up to component isolation.

Summary: Don't spend any money fixing this computer (unless you reeeeeally want to).  Like an older car, it can be difficult to find parts for older computers, but there are places that have them.  My advice would be to use it until 'till you lose it, then purchase a new computer.