Hi VJG,

...hahaha nwala nuon akong pagka lurker diri...re your concerns..
1. Minimum number of PC's para maka break even
- depende sa imung budget, mu break even manjud ka, it's a matter of when..ug willing/determined ka mupadayon sa imung venture.
2. Unsa nga OS akong gamiton this time? XP ghapon or WIN7 na? Dapat licensed jud and mga pila ang magasto?
- depende sa budget og buot/perspective, kung kaya sa imon buot mag pirated, why not coconut, og maprinsipyo ka hala pag licensed, pero it's another cost
3. Asa ko installer ana mga online games and posters? -
Once again, it's either pirated or licensed, either way, mugasto ghapon ka..for posters panghatag mana ang uban ana
4. Unsay patok nga mga games nowadays? Online and Offline -
HMMM most nga magsugud ug iCafe kay either nay background (gamer, IT/Computer related) or MUCH MONEY nga taw..You have to know the industry, bisan gamai lng, don't jump in totally blind
5. Unsay other preparations? -
Being Legal, the usual lang gud...
6. DO's and DONT's -
Use your Background (IE :P
) it's a good fallback, and some mistakes and experiences makatabang pud 
7. Or other things nga akong nalimtan pag mention. -
IMO, in an urban setting, the iCafe is already a mature industry or RED OCEAN, though it doesnt mean na di na sha profitable...it also boils down to location-location-location, kung makapalugar ka sa mga towns diri sa sugbu na di kaau kusug makapatuyang pa siguro ka..pero kung sa ciudad lisod na...Piso2 is OK, but you have to think of the security sa imong PCs kay kasagran way nagbantay ana..most successful style sakong nabantayan kay carederia/sari-sari store w/ hulog2 iCafe sa kilid aron mabantayan rapod..
Good Luck! :P