Mini and constant hangs and beach balls of death

Question

OSX 10.5.8 2GHz 4GB, Safari 5.0
I'm starting to get quite frustrated with my Mini. I'm a power user and it's not uncommon for me to have 25 Safari windows going in tabs in the dock, and running LIghtroom, Photoshop, NeoOffice, Mail, Yahoo messenger, Gmail, Virus Barrier, 1Password, Little Snitch, Text Edit, Preview among other things all at once. I have nearly 300 applications on this machine.
Today I think I was running Chronosync and tried to take a screen shot of something (I use RapidoStart to get apps quick) - so I hit the key to show the apps, and click away on the screenshot widget to get the capture cursor and nothing - so I'm trying it over again several times and no reaction. I give up and a minute or two later I get the capture cursor over and over again 10x forcing me to use it to make it stop, and getting 10x useless captures.
That's just one incident. I'm constantly getting beach balls in Safari. Yes there might be some flash content - though I do also use ClickToFlash to stop most of it. I use Main Menu (handy drop down folder in the Menu Bar for all my apps) - sometimes I click on it and it doesn't react - or hangs and finally works after a looong lag or beach ball.
Sometimes when it's really bad I launch Activity Monitor - if I can get it to react. Safari not responding is the most common culprit, but more often there is no CPU hog or frozen apps on the list. It's just slow and sticky all the way. I do repair disk permissions regularly as well as backups with Carbon Copy Cloner and Super Duper - both.
The reason I got the Mini was to get rid of these problems - same things that happened even worse on my White iMac. Now it's the same stuff all over again. Pre-OSX Macs NEVER hung when I clicked on something - now it's constantly click and grind. I want immediate and fast use and navigation - is that so much to ask?
Thinking about going to a faster CPU iMac model - or any other suggestions would be helpful. Roto-rooter for clogged OSX? Thanks!

Answer 1

Thanks everyone for the input!
I've been through all the standard stuff (troubleshoot the beach ball) many times.
I was thinking that it's just the Mini coming up short on processing power - but I would agree it's part that - but also quite a bit in the way I work. I never shut down the machine - also a good idea to clear out the cobwebs and reboot or shutdown more...
Shovebox is something I have but never tried - running it now to see if that helps - but part of the reason to keep many windows/tabs going is to maintain active logins on sites - and to have fast retrieval, instant participation, and reminders of current items - shopping, research, discussions, blog, webdesign, web galleries etc.
Safari does seem central to some of the problems. I'm always trashing cookies and dumping the cache (something else that causes a mega-beachball). Firefox might be an alternative - but it's not currently working with my wireless Kensington keyboard button and scroll shortcuts for web surfing (possibly could be reprogrammed though?). It also seems a bit slower and is not as well color managed/correct as Safari.
I got Virus Barrier as part of a MacHeist deal - it's subscription has run out though so not something I'm interested in continuing with. Probably worth uninstalling to see if that helps. I never did really run into any Viruses anyway! It's mostly ParanoiaWare, LOL.
I'm slowly transitioning away from the PPC apps.
Interesting comment about not using Widgets - guess they just put them in there to degrade OSX performance so it's more like a PC! LOL
I'm guessing a new iMac might be a big bump in speed as well.
I resisted them and chose a Mini because of the horrible glossy screen. I'm a professional photographer so it is critical to have the most accurate non-fatiguing monitor possible - not the "newest and shiniest" just that looks good in a retail store.
So if the Mini isn't enough computing power and the iMac glossy display *****, there's no where left to go in the mid-range. Probably go iMac and use an external "good" monitor for critical editing work - and the glossy useless one for the web and everything else. A Mac Mid-Tower would be the answer - but nope.
OK thanks again - that's a good start to hopefully improving performance!