Some games deploy techniques that hurt performance of the cpu emulation,
in some cases this affects the overall speed in some it is only intermittent.

First try to rule out some parts of the emulation causing this, like turn off sound
in the game. Then try various settings for the cycles= parameter in the dosbox
config file (there's a full section about performance in the README btw.)

Not all DOS games are equal. The games you mentioned were very demanding back when they came out, even on the fastest processors today games run in DOSBox can run only approaching a level of a Pentium 166+. (but not in all cases and that's with the fastest processors).

Your processor is far from the fastest.

Also verify that no spyware/malware or other processor intensive tasks are running on your system while using DOSBox.

I realize my processor isn't the fastest. But another person mentioned in another forum that my computer should be able to play all these games with a smooth fps. That's why I came here, I want to know if there is something wrong with my computer or with DOSBox. I'll try checking for spyware and tinkering around with DOSBox.

One person's "smooth" is another person's "unplayable". Be sure you both are talking about the same areas being played.

Also most of the advice you hear on the internet about DOSBox is from people who don't know what they are talking about. If it's not advice from here that don't take it as gospel.

good point. Anyway, I'll try the things you mentioned.

are you running these games on fullscreen instead of a window? i ask because i had huge problems in vista when i used dosbox in fullscreen

sometimes and sometimes not. I have problems running them in fullscreen so I usually run them in windowed mode.

why not set your cpu to max in the dosbox config file IF you are already using a fixed cycle rate. mainly cuz in the game doom the more stuff you have going on screen the more it taxes the cycles thus causing it to slow down in frame rate. at least i think im right with where im goin with it.
the only heavy graphics game i played through dosbox was staytooned through windows 3.1 and phantasmagoria and both had moments of slowdown only when being read from cd.

why not set your cpu to max in the dosbox config file IF you are already using a fixed cycle rate.

Neither does this sentence make sense nor would, reading it either way, this be a good suggestion.

Does profiling aided compilation help at all on these cases?

I'm wondering also if it would be possible or even desirable to emulate at the dynarec level some techniques of modern cpu's (out of order execution for example)

Does profiling aided compilation help at all on these cases?

Only if e.g. graphics output (scaler etc.) are source of the problem.

to emulate at the dynarec level some techniques of modern cpu's (out of order execution for example)

This indeed may work, given that the recompiled blocks live very long (this is
not true for several heavy-games though). Can't think of any reordering/pipelining
or whatever that may help though.