Acer tl-64 upgrade opinions and advice

i currently have an acer 5517-5358 and im debating a cpu upgrade.

current system:
320gb Scorpio blue hd
2x2gb hynix 6400s ram (Max Supported)
windows 7 home premium 64bit
tk-42 1.6ghz amd 64x2 dual core

avg core temps of 39-41c under normal use
i dont overclock and have never attempted due to risk of my lack of knowledge in overclocking. my computer is fairly fast (windows rating of 3.2) for what i use it for but sometimes lags when opening larger video files.

my basic questions:
-is on a scale of 1-10 how much will i notice in terms of a speed difference in the pc?
-is it worth doing since i have the know how and a few tl-64 2.2ghz amd 64x2 dual core cpus from broken dv9000s models?
-will the cpu effect my graphics any? (i assume not, due to the gpu being a main factor)

I wouldn't bother in a laptop. The cooling was designed for that specific processor, and any change could result in overheating and possibly damage to the system. OEM laptops aren't meant to be upgraded (in terms of CPUs).

I'd save the money towards a new laptop.