I have an Acer 4730Z laptop. It has this processor --->Intel® Pentium® Processor T4200 (1M Cache, 2.00 GHz, 800 MHz FSB).

Honestly, I don't understand very much of what that means, and I don't really care to. What I do care to know is what processor can I buy to replace it so I can run ProTools8 comfortably?
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Over the years of running ProTools, both on Mac and PC, I've found that RAM is much more important than CPU speed. A faster CPU isn't a bad thing but beefing up your RAM, I'd say at least 2 Gb, is usually a better idea.
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I'll explain it this way:

Your laptop is as powerful as the first PC I ever used. 8 years ago.

As grunion said there are very few PC's that let you replace the processor, and laptops less so. A new computer is in order.
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With pedals you can throw your guitar down for an impromptu pedal drone solo, whereas if you did that on a rack it would just look like you were programming your washing machine.
It'll be fine, I've done 16-track recordings on a 1.4Ghz Athlon T-bird so there's no reason to go and buy a new laptop just for home recording!

You've essentially got a 4Ghz processor there, along with 2Gb of RAM, which is far more than enough.

Just pay extra attention to getting a good sound right first time (you should be anyway) and computer specs are almost irrelevant - as you don't have to use as many plugins or virtual instruments to 'fix it in the mix'