Ok, I have Inspirat Brickopack installed on my old computer and I never had a problem, everything installed fine and I love the skins, awesome. So I just got a new desktop and after I installed Windows and SP1 and 2 I tried to install the pack. It worked... for the most part, my task bar and windows are still XP style and under Display > Appearance there are not the Aero or Inspirat options in the drop down menus. I checked on my old computer and the same folders will the shell.dll files are installed in the same directories but for some reason it's just not working. I tried uninstalling and reinstalling the pack and that didn't work either. What can I do?

pasttiger, The bricopack installation to your new PC may have been interfered with some other installed programs of yours
So uninstall your bricopack and try re-installing it on Safe Mode

To get the custom styles working, you need to patch a file called UxTheme.dll
If the Bricopack has failed to patch the UxTheme.dll, you need to do it manually.
 
To patch the UxTheme, download and run the Patcher (for Windows XP) from:  
 Here for Windows XP SP2.
 Here for Windows XP SP3.
 
After you patched, reboot, and try to change the visual style.
 
By the way, nice to see you here again, Neil

Thanks Legace Actually I've been busy with ward works (I know you can imagine )

pasttiger
What Legace says is one of the possible things that moght have happened during your installation of the bricopack
This is mainly due to some other software applications or programs which can interfere with the replacement of files done with Bricopack installer (eg:- Antivirus Software, Firewall & other backup utilities)
That's why normally it's suggested to install the pack in Safe Mode

Offtopic* God I can't imagine how many times I've emissed this

But as an alternative, when you've already installed the pack and you're only having the problem with the Visual style, you can manually patch the .dll as said by Legace