Well I bought an dell dimension 3100, pentuim 4 HT extreme editon, thin is when i bought it was super fast and 3 years later its slowing down to nearly a crawl.

Can you help me, caz i have not done any physical modifactions and ihave done 5 things to speed up you're pc still slow, Like HD Defrag cleaning up temporay itnernet files.

I Have installed and unistalled a Lot of programs, HOWEVER , it is something to do with the regisrty is it?

You could have viruses and or spyware which can slow down your computer. I've found that after some time windows gradually just slows down, which is why I format my drive and install windows every once and a while.

well i did a registry cleaner ((but i backed up the registry first) and well it's back to its normal fast state, however MSN does slow the pc down when starting , it took my Mums vista laptop 10 mins to load msn before it was working normally.

How much free space is left on the hard drive?

Do a disk cleanup,check all box,s.

Try this:CCleaner - Home

Which drive do you format? Because, if you do a format on either drive, if you partioned them as two different drives, wouldn't lose data either way? If not, could you explain how thats done?

How many drives do you have? If you have more than one, you only would format your drive that the OS is on. The other drive would store any files you want to keep.

If you had 2 partitions you, then you would treat it as though you have two drives when formating. But make sure you format the right partition(make them different sizes?).