I wish to buy a notebook as a desktop replacement. I do not care about the battery life. I care about the ability of the machine to process heavy tasks in making video (divx, mpeg, dvd, etc) Which CPU is the best for this specific work? Is it the 1) Mobile Intel® Pentium® 4 Processor Supporting Hyper-Threading Technology, used by the Toshiba Satellite P30-132 (552 model) 2)Intel® Pentium® M processor, used by the the Sony Vaio VGN-A397XP (760 model) or 3)Intel® Pentium® 4 processor, used by HP zd8000 series (550 model). All of these CPU support HT technology. But is the 2.0 GHz with 2 MB cache L2 more powerful (ofr video applications) than a 3.40 GHz with 1 MB cache L2, or NOT???

Pentium M processors do not support hyperthreading.
If the application you use for editing has multithreading (multi cpu) support then the cpus with hyperthreading might have a slight advantage.  I'd say a 2ghz Pentum M is about equal to a 3.2-3.4ghz Pentium 4.  If you don't care about battery life though I wouldn't worry about spending the extra money to get a Pentium M.
One note though, pretty much all the laptops with Pentium 4 processors are VERY loud.  They require so much cooling there really isn't any way around having a big fan noisy fan in them.  If that is going to be a problem you might lean back towards the Pentium M.
 
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