Dedicate one machine to trading and banking, put it behind a whitelisting firewall. learning to whitelist is doable by anybody that can trade... at that point, it matters little what operating system you have but make sure you have the OS disk and learn to do a format and install. It might be good to get the software from the disk drive manufacturer and do a true low level hard drive format... 1) set up firewall 2) format the hdd 3) install the OS and trading software You will NEVER have any problems with your computer. No need to do OS upgrades at all... no need to be careful what you click on either, click away, your firewall is not going to allow you to get in trouble... 4) Get a second computer. Get a MAC and get on with life...
For Windows 7: Create a new folder and name it "control GodMode.{ED7BA470-8E54-465E-825C-99712043E01C}" and the folder icon will change to a control panel icon, and you can use that to see/change all your settings. Enjoy.