Ok I own a Mac... an iMac, the bubble base kind and it has been an awesome computer but lately my family and I have been having trouble with it.
We use Safari as our main browser for internet but I really hope that isn't the case; what has been happening is our windows and what ever we have open and are working on will keep bouncing up and down and won't stop. Well it does but only if it wants to. Can you help please, because even as I type it hides away like I've pressed F10.

The icons in mac bounce when they want alert you about something. Like a warning or a message.

Not the icons I know they bounce
The whole windows bounce as if I've pressed F10 many times in a row

My Imac is very slow at start up, by passes my log in, goes directly to my desk top, then takes about 5 minutes before I can click on anything. Then in 10 to 15 minutes it freezes up and I get the spinning color wheel. It will spin for hours if I let it, I have to turn off the computer manually.

My iMac screen turns blue after power up... how to solve it?

my imac screen turns blue after power up...how to solve it?

What model iMac and OS. Did you hear the chime?
Did you see a apple logo with the gear spinning?

Some how I have acquired on my iMac a black bubble with a white outline which carries 'advice' as to some of what's happening - word processing/searching. If I turn on the volume I also get the same advice verbally. So I can't, e.g. listen to tutorials. Help! How do I get rid of this?
Ginny