Few things - To flush RAM, you don't need to hold the power button for 30 seconds. A second of power loss is enough to lose what's stored in RAM. At any rate since this is intermittent that's not going to help prevent the issue form coming up.
I have never seen too many programs running cause this error. Usually when too much is running you'll get messages related to insufficient memory. That said disabling running programs wouldn't hurt. Basically, all you need running at startup is anything by microsoft, anti-malware/virus software and drivers. The rest can be disabled.
Now this error message typically comes from 3 sources, bad RAM (memory), bad sectors on a hard drive and a corrupt program. When does this error typically come up? Is there any action you do that seems to trigger it? Based on what I see online this could be caused by one of the programs that installed itself into the right-click context menu going corrupt. Right click a file, make note of all the programs listed there, uninstall and reinstall them all.
Download the two programs below (they'll both in .iso formats). Using a program like IMGBurn, burn the "image" to blank CDs. Starting with Memtest, boot from the CD and let it run over night. If any errors are reported, you have bad RAM. Do the same with Seatools after that, running the long test in there.
Memtest86+ - Advanced Memory Diagnostic Tool
SeaTools for DOS | Seagate