can't do normal startup

I'm trying to check to see if I have a malware problem but I cannot start my computer in normal startup mode unless I leave the box unchecked that says "load startup items".

Is that ok to run spybot and other programs when I don't load all of the items that are listed in the startup tab?

I'm not sure what the problem is I am having but if I load all items in the startup folder then my pagefile grows until it's at 4 gigs and all I get are out of memory errors. If I don't load all the startup items and run more of a selected startup items then it loads ok and I can run programs. So again is it ok to only load selected startup items to run thru the programs you have listed?

"Remain in this Normal Startup mode while your PC is being cleaned of malware"