Internet Explorer 6 s-pack 1 windows 98

I have the following PC – Pentium 350MMX with 256 MB Ram. I have Internet Explorer 6 service pack 1 installed.
The problem i have is this:
When i log onto the Internet i get a 53,333 k connection at all times through my 56 k modem but when i click on a page it can take 20 seconds for the little blue indicator bar to start moving. This also happens with hyperlinks too. The problem is periodic and i can click say 20 hyperlinks and have no probs then i click on another and it will simply lockon me for 10-20 seconds as i have stated before. If i open a new browser sometimes this kicks the first browser into de-locking so to speak. I have two different types of memory 2*64 MB PC 100MHZ & 2*64MB PC 133MHZ. Could the problem be caused by incompatible memory?