Strange ‘white screen of death’ problem

Hi, i’ve scouted numerous webpages with fixes for the wordpress white screen of death but my problem seems strange and really hard for me to troubleshoot. The problem is my site will run OK for hours even a days and then all of a sudden for no reason all goes white on both the website and the admin pages.
I’m pretty sure its one of my plugins as when I deactivate the plugins folder by renaming it and add an empty plugins folder the site comes back up, trouble is I can’t work out what plugin it is as once I reactivate the original plugins folder the site carries on working OK.

I’m using wordpress 2.9.1 and the plugins installed are:
Advanced Text Widget
Akismet
All in One SEO Pack
cforms
My Page Order
NextGEN Gallery
PS Auto Sitemap
Simple Image Widget
Simply Show IDs
Smooth Slider
Wordpress Backup (by BTE)
WordPress Database Backup
WP-DBManager
WP-Table Reloaded

Does anybody know of any problems with any of the above plugins?
Any ideas on ways to fix this would be greatly appreciated, my site is pretty much done but don’t want to go live until I have sorted it.

Thanks in advance
Karl