just did the same thing here.  2.2ghz with duo core etc etc. and Vista 32.

Live in the Control Panel for 3-4 hours and you will be fine.

1st thing - turn off all the new bells and whistles.  Just select Classic where ya can.
2nd thing - turn off the permissions.  This is the feature that asks you every damn mouse click if you really want to do what you thought you were doing in the 1st place.
3rd thing - uninstall all unneeded programs and games and trials etc that came with the Dell.  My Acer has a 500gb hd and 200gb was filled with uter crap.

I still hate the new File Explorer and how it thinks it's really groovie to tell me all about my mp3 files and my pictures and my applications.  I like classic, I couldn't figure out how to change this back.

I did all this with my fathers new Dell - the machine was basically dead to him and he couldn't install any games etc.  I spent 13 hours cleaning and turning everything off and now it is a screaming machine.

Vista is so much faster with the duo cpu and a lot of memory, my machine is blazing fast now, but like you when I turned it on out of the box is was a complete frustrating joke.

Stick with it, just keep turning crap off in vista and go with classic as much as possible and I think you'll be happy in the end.

oh and remember to breath - and if ya smoke cigs - many many cig breaks!