Video Editing... PC Spec

I’m currently doing some video editing and my computer seems to struggle.

I’m using premier pro and as I play back my video footage after editing I seem to get a “lag” and the video skips and jumps as if it cant play in real time. Some edits skip completely which makes it near impossible for me to get clean cuts between footage.

Is there any settings I can change to help solve this?

also I don’t know if this is also related to my computers power but I cannot seem to import files over 100mb it just freezes up and the import loading bar comes up but then after 5 mins or so just crashes out and I have to close it…

Here is my computer spec

Intel Pentium® 4 CPU 3.20ghz 3.20ghz
1.00 GB of Ram
250GB Hard drive
Nvidia Geforce 6600

I have a feeling it could be a “ram” issue would upgrading my ram make a noticeable difference? or would I benefit more from having a better graphics card?

your thoughts, opinions, help and guidance are greatly appreciated…