I restrict my OS partition to Windows XP and security programs (Firewall, AV, AT and AS), restricting it to about 4GB actual size so I can backup this partition to single-DVD media. For partition size, I simply set my OS partition size to 8GB.
How are you measuring start-up time? If Windows is fully usable after 41 seconds, I don't think that's slow at all.
Some things you can do to improve boot-up speed:
- Trim your start-up apps to the minimum.
- Trim your processes to those actually required (the Elder Geek's site is excellent).
- Periodically clean and defrag your OS partition.
My own boot-up time is nominally 40 seconds with:
- Software firewall (IS2005) at startup.
- Resident AV (IS2005 PC-cillin) at startup.
- Resident AT (Trojan Hunter Guard) at startup.
- Resident AS (Spy Sweeper) at startup.
- 21 running processes at startup.
I can't do any better than that with this system config.
Hope this helps!