T60 Hybrid SSD-HDD, couple of questions

[Wind]

1. I found somewhere (some well known IT site ? - can't remember at the moment) that in case of storing op. system (Win7 in my case) and other software on SSD and rest of data-files (documents, photos, movies, music...) on HDD "it does not matter how fast is HDD..." !? Author means it does not matter for general hybrid-laptop performance (in that configuration SSD-HDD) how fast is HDD...???
This is very interesting, as I rejected 2 Scorpio Black coz of vibration/noise and I am looking for 500-750 GB HDD to be extremally quiet and I ma confused if I have to stick with 7200/16 or 5400/8 is equally good for me ?
2. I use fantastic free Advanced Sustem Care for keeping discs and Windows in good shape. (they also offer one of the best available defragmenter in package). Does that makes sense to defragment SSD ? I heard its pointless.
3. I noticed my T60 has 802.11 b/g card and signal is much weaker than on my T43 (currently broken). Which card would you recommend for T60 & Win7 ? I found Gigabyte AirCruiser N300 review claiming its faster and provides better range than Intel and Atheros based cards...can anybody bring some light here ?
4. I am also interested to replace CPU on my T60 200746M. Currently I have 1.83 Ghz Dual Core. Would be graet to know which is the fastest CPU I can use and if that is effective ? I sthat good idea or wasting time and $ for any reason ?
Thanks in advance for any help.

[mgo]

1. I found somewhere (some well known IT site ? - can't remember at the moment) that in case of storing op. system (Win7 in my case) and other software on SSD and rest of data-files (documents, photos, movies, music...) on HDD "it does not matter how fast is HDD..." !? .

I am using the Intel X25-M solid state drive on three different T60 machines with excellent results. Windows 7 will notice the SSD and disable defragmenter for it. (Defrag is not needed with a solid state drive) You may also want to disable Prefetch and Superfetch, but it does not seem to make much of a difference. Do not disable indexer or Search as some suggest. That is a dumb idea with no real reasoning behind it, and it cripples Windows 7 badly. No need to disable virtual memory either.

My drives are partitioned for the operating system and program files located on C:\ separately from the D:\ partition which contains my documents. This makes managing the C:\ partition easier when imaging the drive, etc. Multimedia programs are on a second drive in Ultra Bay. Yes, the speed comes with having the operating system on the SSD. Multimedia files come up very quickly, because the operating system calls the files so much faster.