Help with COMPONENT & HDMI

Okay 1st off i wont say i am new to the ps3 cuz i got mine since 2007 but i am still unsure as is it necessary to buy a hdmi cable to play some games?

I am living in Uk & got the us Ps3 (if this is any helpful bit of information as i am talking ps3 games specificly) but there are some games that just wont play on my normal componet tv (with rgb cables) e.g

1. Heavenly sword - disk

2. GTA4 - disk

3. Tekken 5 -psn download

4. Medievil-psn download (a ps1 game though!) (at 1st i would have thought all psn games would result in this, but sf2thdr works like a charm & so does mk2, & that "elephant bridge building game" )

However moving the console to the kitchen where i have a hdtv (19inch screen only) and using the hdmi cables lets me play them. To me this is strange as are sony saying you must buy a hdtv just to play some games or is it me not setting the video out put right.....(cuz i am sure some other people may not have this problem)

I am not particular about picture quality (just yet! lol) as I am just ok with fairly decent quality(which is what i get on my samsung dvb 32inch with free view so i know its a digital tv)

any idea as to what kind of configuration i should be using on the component cables to show these games?

Thanks !!!:)

not true when i had heavnly sword i still had standard tv it works fine