Improving Win XP System Performance?

Ok I need to know two things.

1.) It doesn't matter whether I use Normal or Selective startup, evertime Windows boots, it puts that damn Windows Messenger Icon in the tray. I tried to disable it in selective startup, but it just takes longer before it shows up in the tray. Once I'm at the desktop, it takes literally like 3-5 min. to get to where I can do something. I'm also running Norton Anti-virus w/ auto-protect enabled. When Windows boots, the Norton tray icon appears, but has the red "X" through it. Then I wait like 5 min. for the Windows messenger Icon to load to the tray, and then the Norton auto-protect is enabled. So what's the problem? How can I get rid of Windows messenger in the the tray everytime I boot? Also, does Norton just take awhile to load, or is it related to the Windows Messenger loading in the tray?

2.) I want to upgrade my system. I currently have:

HP Pavillion 8700
Clean full install of of Win XP Home (I formatted the HD w/ win 98)
128 SDRAM
30 gig 7200 RPM HD
40 gig 5400 RPM HD (Music and Video Storage)
AMD Athlon 750 Mhz
New TDK 32 Speed CDRW
DVD drive (Now a cdrom drive since I lost my WinDVD when I cleaned off the hard drive, and no longer have the dvd filters)
SB LIVE! Value (Messes up sometimes w/ my Klipsch surround speakers!)

Question is HP components are not ATX compatible right? Basically, what I want to do is gut the HP and build a new computer w/ more memory, motherboard, and Athlon XP processor. I'm going to use the same HDs and CD drives. Does HP do what compaq does and not have separate components for sound card etc.? Anyway I want to do this eventually, but now I'm really just looking for more speed. When I go into Win explorer, it has to look for my DRIVES! with the flashlight sometimes. If I double my memory how much will that help my problem Thanks

-Jeremy

Open Messenger
Tools -> Options -> Preferences tab
untick "Run this program when Windows starts"
untick "Allow this program to run in the beackground" (to stop OE)

For MSN:

1. Change the prefs within it
2. If that doesn't work, use msconfig
3. Sites like Hotmail turn it back on, as does Outlook and OE. There are prefs to turn it off within Outlook and OE, but I don't see any in Hotmail.

For speed:
1. Turn off the bloody ugly visual themes
2. More memory will help a lot
3. Make sure XP is on the 7200 RPM drive
4. Burning the HP logo (nice printers, crap everything else)
5. Consider NTFS...it uses variable cluster sizes rather than the fixed size of FAT and FAT32

Don't bet a penny on any Compaq or HP component being standard. Doubling your mem will make a huge difference.