emulator problems

first off i want to say hello, im travis 92 and im new here to this forum, nice to meet everybody

second, the issue at hand, basically ever since last summer my computer randomly shut off one day, and it wouldnt tur on for a day or two, and then it suddenly came back on, prior to this my emulators that i used were working fine, like they should, despite the age of my system, and then when the comp came back on it wasnt the same, the emulators are slower, and its gotten worse

for example, the sound in the epsxe 1.6.0/1.7.0 is stuttering, and ive tested every plugin and when i hit test for sound, nothing happens

the emulator skips and stutters in visualboy advance 1.7.2/1.8.0

no$gba2.6a was working fine before but now it goes much slower

chankast and project 64 suffer from the same issues as no$gba

ive even restarted my computer, fresh, with windows service pack 3(originally 1) and i suffer from the same problems still, its been racking my brain ever since last summer and im not sure what exactly the cause is, i was wondering if someone could help me on this issue

im thinking it could be hidden bugs or something, because i ran virus scans and nothing came up as bad or malicious.

btw here are my system specs....

windows service pack 3
128 mb of ram
28 gb harddrive
2.00 ghz processor
dell dimension 2350

any help or thoughts would be greatly appreciated, thank you in advance