low FPS?

You may have played BFBC2 on medium settings, but with that 4550 I doubt that it was actually playable. One of the better roundups about BFBC2 performance,

Battlefield: Bad Company 2 GPU Performance In-depth > 1680x1050 – High/Medium/Low - TechSpot

Considering the 5570 barely made it past 30 FPS on low and is anywhere from 1.5-2x faster than the 4550, playable just doesn't seem possible with your card.

Think the biggest problem is you are expecting mid to high end performance out of a last generation low end card, which just isn't going to happen. Your card meets the minimum requirements for both of those game just, and falls short on the recommended,

Splinter Cell Conviction System Requirements - VGRequirements Forums

Battlefield: Bad Company 2 System Requirements - VGRequirements Forums

Minimum means the game will run on low settings, playable is another story. Recommended means it will run and usually be at least playable on low settings.

does he mean HD 4670 in splinter -secommended or what is that radeon 4650?

*recommended

4670, which again is almost twice as fast as your 4550. You have to remember that there is only one card lower from the HD 4xxx series than yours, and that is the HD 4350. Those cards were never meant for games like BFBC2 and SCC, more for light gaming and for HTPC's with more features than onboard video (Intel's mostly).

You want to play those games at anything that remotely resembles playable frame rates (and 20-30 in BFBC2 is not playable, and no doubt goes even lower once there is smoke or dust) with that card you're going to have to set everything to low and select a lower resolution than the 1600x900 you have showing in your specs (try 1280x720 instead). Either that or as has already been suggested, you need a better video card than what you currently have.

so ....... does this pc deserve a better video card .... or the pc is a load of junk ... i mean when i buy a new video card will these games run better (i know i need 2 more gbs of ram but that can wait) or the pc isn't good enough ........
also when i buy a new kinda cheap card GT400 or something will it work for a while on new games or it will turn up like this one (i am not a graphics enthusiast i just want 40/50 fps and i can even turn it to med if required ... i just want a playable game ) so how much do you think a GT400 will work (with this pc)
you know when i play SCC in realistic .. then someone detects you ... then the game freezes .. you just become sure your dead .. keep my finger on the mouse waiting for it to come back so i can try to survive
playing the game and finishing it in this crap way really makes me a pro lollllllllllllllll
thanks for listening .... i mean reading
lol

ok i asked a question that you forgot to answer and here it is again:
when i buy a new kinda cheap card like GT240 or something will it work for a while on new games or it will turn up like this one (i am not a graphics enthusiast i just want 40/50 fps and i can even turn it to med if required ... i just want a playable game ) so how long do you think a GT240 will work with me?