Best for editing AVCHD - Final Cut or iMovie

Question

Pretty fundamental stuff, I guess, but I have an iMac with 4 Mb Ram and 1Tb storage. I work in a school and record footage on to a Canon HD camcorder. Sometimes I can import direct into iMovie and struggle to get a 2 hour end product to fit onto a DVD. Sometimes the import fails and I have to 'log and transfer' from the Canon to Final Cut 7; do titles and effects etc. then try every which way, in vein, to try and create a DVD.
If I export a quicktime movie from Final Cut it's like 100Gb compared to iMovie's 5.5Gb.
I've now got in a bit of a mess - there's clips, sequences, iMovie cache folders, PAR folders, iDVD project files, DVD Studio projects and .mov files all over my Mac. I keep running out of space and don't know what I can delete, because it's not apparent what belongs to what in the grand scheme.
Is it foolish to use a domestic single chip AVCHD camcorder with Final Cut Pro or can I just convert the AVCHD file in some way before I edit nd output it ?
Any tutorials on this stuff ???

Answer 1

.. First off I know nothing about iMovie, but plenty about FCP. ..
+vice versa+ here ..
FC/p is +by far+ superior in its editing features compared to iM, for sure.. but bertieonamac's Q pointed into a diff. direction, and I dare to say, four your needs, the iLife-siute of apps is 'better'.
why?
a) Organizing.
iMovie09 automatically sorts into 'Events', based upon the assumptions, the recordings of one day are 'one' content. you can re-arrange that, build your own Events, change time-stamps, organize via keywords/tags. with a click, iM sorts you all content with 'Suzie/Goals/Explosions/...' iTunes for videos ..
FC/p 'allows' storing material anywhere & anyhow .. if you are not disciplined = clutter ..
b) Convenience
80% of features, an average project needs, are offered by iM09 - from a bundle of dissolves, to cut-aways, green-screen, pic-in-pic .. for another poster, I made this web-site
http://sites.google.com/site/karstenschluter/how-to-make-a-vidcast
to show a few options, iM09 offers.. done 'within minutes'
FC/p is a professional tool - it allows much better control, but asks for in-depth knowledge (example: Ken Burns - in iM start/end, in FC/p you have to understand the concept of key-frames etc)
c) Simplicity
if you respect the restrictions, iM gives, it is 'plug'n play'. not every cam is supported, not every rec-mode is supported. the app itself has hundreds of limitations, two examples: a dissolve's length is max. half of a clip; only one 'effect' per clip .. etc etc. if you respect this limits, you don't have to care
for codecs, aspect-ratios, renderings ..
FC/p allows 'anything' - including getting-lost ..
d) Concept
iDVD is limited to 120min max., incl. content in the menus. you told us, you struggle doing so.. it is simply not possible, by concept. shorten your project to 110, don't add 'movies' to animated menus but simple stills - done.
the 'share to iDVD' feature of iM uses a totally different setting in encoding than the simple 'Export QT'/timeline' feature of FC .. therefor a very diff. file-size ..
I dare to say, you don't know about how FC exports, nor about encoders.. iLife is a consumer-product.
FC/p asks for a in-depth understanding of video-technology. e.g. Compressor overwhelms the average user with zillions of options... FC/p is meant for someone, who uses these tools 8h/d ..
summary:
'Best for editing' - FC/p
'Best for editing on a consumer level' - iMovie09
.. independently of the codecs the cam uses ..
and Welcome, bertieonamac, to the  boards ..