Issues with trial version before buying

I downloaded the latest 64 bit trial version the other day to see what I think before I buy, I was using Comodo previously, uninstalled it properly and cleaned the registry.

But since I have installed I have these 3 problems

my internet has slowed down (some times doesn't work at all). If I untick real time monitor, it doesn't stay unticked

I got so annoyed and downloaded the latest Antivirus, but had nothing but troubles with this, when watching dvd's or avi's or playing games the computer would just freeze and I would have to reboot.

I am using Vista 64 with all built in security turned of

Any help would be appreciated