Q: Last couple of weeks my imac is fairly regularly freezing just for a few seconds then it unfreezes and then freezes again. It continues like that for a while then it seems okay then it does it again.  Do Imacs need a cleanup?

Have a look through the log files (Applications - Utilities - Console) just after it next happens and see if there are any system errors being logged.

Gail1358 wrote:

 

... Do Imacs need a cleanup? ...

Not as such...

See Here for keeping your Mac Happy...

http://support.apple.com/kb/HT1147

http://www.thexlab.com/faqs/maintainingmacosx.html

Mac OS X: About background maintenance tasks

Gail1358 wrote:

 

Last couple of weeks my imac is fairly regularly freezing just for a few seconds then it unfreezes and then freezes again. It continues like that for a while then it seems okay then it does it again.  Do Imacs need a cleanup? What could be the problem?

No but if they have in-adequate amounts of RAM they can slow and beach ball. If you have not upgraded the RAM then you can tell if you need some by opening Activity Monitor (Applications - Utiltiies - Activity Monitor) and click on the System Memory tab. As a general rule of thumb if your system has 500MB or less of FREE RAM available it needs an upgrade. You will see a graphic that looks simliar to:

OK, keep AM running all the time, next time you see a freeze let it free up, check again and also while you're in AM look for any applications that are using a large %CPU. You don't check for FREE RAM when everything is running perfectly, you check when you see performance issues.