Administrator rights

Perhaps a dumb question ? Since I am the only user of my laptop at home ( Windows XP Professional v 2600), to enhance security is there any reason what I should not disable all users ( user, Power User, etc etc) and just allow myself as Administrator? This surely enhances security. I understand I will need to keep ASPNET ( or do I ?). Seems logical to me, but nobody has ever suggested it? Any comments please ?