Second day using Mandriva Spring Edition on My Acer Laptop

Hai, i already update all software and i also now can use my nokia 2115 as modem trough my Acer laptop. I just try to get reconnect again with my Nokia 2115, the internet connection is now work and stable. But comes another problem, i use Mozilla as my browser and use some add on on it and the problem come, the screen sometime get blank and flicker. and the worst is the system is hang so i need to restart my acer laptop. After several time the system hang i decided to change the Linux OS again..this is get me frustrated and think to back use Microsoft Windows as my OS on may Acer Laptop. When i want use linux, may be i can run Puppy Linux from the CD :)