UPHClean for Memory Release
I had the same problem with XP: excruciatingly slow logging on and off, and memory freezeups. I went to Microsoft and downloaded and installed UPHClean (user Profile Hive Cleaner) which has an excellent READ ME included. UPHClean opens itself on startup and when your PC shuts down it forces release of all the (memory) handles that accumulated since last shutdown, releasing memory back for use. Better than adding new memory, simple and automatic.