Freeze up

be under tech Q&A, and you are quite vague. you don't give much info.

I'm told by a computer rebuilding company (recomp.com) that heat transfer paste dries out under heat sinks, so heat builds up in older PCs. you might have spyware, but this is likely to freeze your PC when you start IE not just sitting there.

you might install sysmon, which would log what event happened when it freezes. if not same event each time, likely hardware. you can monitor mb, cpu temp in bios

1) I agree that this should be asked as a Tech Q&A, but since you are here:
2) If the time is consistent, regardless of application or peripheral use, it's likely that something is getting hotter than it should, so check that all fans are running, that there's not too much dust, that filters are clean (if so equipped). You could run it without a cover and see if the time changes. Also, depending on what OS, see if there are any event log entries when it freezes, if none, that suggests a hardware problem that we all suspect.