I use Adobe Premiere to edit videos, but the files are so large it crawls.  I use a pc Windows 7 pro, Intel i7 board with 8 gb memory, Nvidia 550 ti with 2gb.Is IMac better with video editing than PC?

I did my first video edit with Adobe Premiere.  I also thought it was a little buggy and slow, especially when I uploaded it to you-tube (the transitions changed).  I did some research and there are plenty of options, but I think much depends on personal preference and overall skill.  Do some searches.  I played with Filmora, Movavi, and others before giving the nod to Movavi for $60.  So far I like it.  Good luck!

Most people would probably say the Mac is better for editing.  I think they both work well.  Personal preference ; )

What i do when editing my footage in Premiere is use proxy files. I convert my video's to a lower resolution/bitrate using Adobe Media Encoder (included in CC/CS6), then i use these files to cut/edit the footage. When i'm pleased with the edit i throw in the source files and apply color correction and grading and finally export the video in the full resolution/bitrate.

Here's a nice tutorial on how to load proxy files in Premiere:
And another tutorial on how to create proxy files in Media Encoder:

Big thanks Lorenzo!!  That was a big help and a boost to my editing.  I feel like I advanced a little in my understanding of videos and Adobe Premiere.  That will be much easier.