Ubuntu8.04 Hardy->surprisingly annoying slooow motion

Hello everyone!:)
I checked many questions and answers here,but I couldn't find exactly what I need...So Ubuntu is running slowly-when application is started it takes about 15-17 sec,when resizing window - it's a Stephen King's nightmare,booting is also takes much time to finish.. (at least the internet connection is very good) ; windows vista runs very well at the same PC.I followed these instructions: news.softpedia.com/newsPDF/Optimize-Ubuntu-8-04-for-Speed-86405.pdf - "but nothing nothing ever happens I and wonder";
Also I did some more like hiding icons in the menu,optimizing the theme (clearlooks)... i would say that the effect was 15% different from situation before .The swap memory behaves well.The drivers for `Ati radeon xpress 1100` are installed.It might be , because of the CPU ( when I "add to Panel" CPU Frequensy Scaling Monitor" it says "CPU frequency scaling unsupported"; In hardware testing -> "The following resolution was detected + impossible with fglrx" ;

Core 2 duo : Genuine Intel(R) CPU
Memory : 1024 MB
Graphics : ATI radeon xpress

hope you can help me. P.S. sorry if it is too long and that my English is not exactly perfect :)