Don't know what your drive is, but it will be the drive, not the interface, that costs you performance.  ATA 133 is 133MB/s bandwidth, far beyond what that 200GB drive will likely do.

The top end modern disk drives will pull 200MB/s max, sustained around 160MB/s.  Odds are your IDE drive you've got is more in the 70MB/s range though, 200 is pretty small to be current tech.  Your failed drive was probably south of the 133MB threshold, but it's cache would have put a great deal more spring in it's step for small write operations.

If you're falling off the SSD bus though, your performance loss will be cataclysmic. 

Yeah, you're going to notice a performance hit going from SATA to IDE; however, if you have an IDE to SATA adapter you can reduce that hit to some extent.  Do not expect a huge difference, though.

I mostly just cruise the internet, run really old games, and use Microsoft office all day. Would i see much of a slow down?

Kona I've gone back and forth between SATA and IDE a couple of times and honestly, it's not a big deal.

Sure a smooth-running SATA will be a little smoother than a smooth-running IDE, mainly for huge files such as DVD or DVD temp files, and of course a little bit up front for boot.  A smooth-running IDE is however a clear improvement over a sputtering SATA - sometimes drives are out there sputtering for a while before actually failing, and that will suck your machine down.  As psycoak said, a lot of it just depends on the individual drives.

I'm on an IDE root drive right now after being on SATA and it doesn't bother me a bit.  Now I have to tell you I don't stare at performance numbers, seriously that stuff can make a person crazier, I just want things to work well without throwing piles of cash at them.

I just had a thought that really drives home my opinion of it:

Last time my root drive died I had the option of re-loading to a SATA or to an IDE, both at no cost.  I re-loaded to the IDE simply because it was easier and faster because of formatting and file-shuffling.  That pretty much tells you what I think about it. 

SATA shmatta.

Say the word and I'll send you my muthaboard:

^  

My motherboard's just like that, only I have the deluxe version with the little hamster. 

Great, DaveRI. You show off!

You belong to the 1% so you just gotta brag. 

Yep, that's me, just rollin' in the hamsters. 

I got yas both beat. Mine has three rubber bands, ultra deluxe.

Good choice Uvah, don't have to feed the rubber bands.  I've gotta feed that darned hamster, and he's a chubby little sh*t too. 

Finally!

My drone photographed DaveRI's computer!

(sans hamster droppings)

Now that's a neat system Doc! 

 Nice pic.

Caught the little guy doing his usual I see - thinking about lunch.

Good job getting the drone past my air defenses too - my buzzards must have been napping again.

Buzzards, you say? Hmmm...

Oh well...

How was your dinner, DaveRI? 

Ah, so that's where the ol' buzzard went.  Knew he wouldn't just go AWOL.  I'll bet he was a little stringy, hope you doused him in some BBQ sauce.

Cool drone    I want one that I can buzz around and zap hornets.

Probably not a big one.  Your machine might boot a little slower and you may notice some slow down while handling large files ... copy, move, etc, but if you are just net surfing and playing a few old games I doubt it'll matter too much. 

I know this is silly of me, but I'd think a guy who repairs computers would know this simple stuff by heart.

I think a certain someone might chime in at this point with a ....... " BAZINGA ".....hehe

On topic:

@ kona

By now your google/bing searches will have told you more than the responses in this thread, besides which why is your question even relevant to your situation in the first place?  Don't you suspect your main drive of failing?  Isn't this replacement the only other drive you have?  So swap the drives and you'll get the answer to your own question with the benefit of having some additional knowledge for when you provide your services to others.

Hey, what do you want from a guy who bases his diagnostics on a .......

A real tech would use a Ouija Board.