iMovie HD/iDVD Project Length for DVD's?

[Dream.Finder]

Hello all,

Just a few questions. I am *nearly* finished editing a vacation movie project and it has turned out being around 3 hours and 43 some odd minutes long. The max length my DVD-R discs can hold are two hours, so I know I'll have to divide them between two discs. My question is this...

I am planning to add chapter selections and menus to both part 1 and 2 of my discs, complete with music and simple still pictures for some of the drop-zones. Will my disc be able to accommodate that? How long should I each section of my video be chopped down to (for each disc parts 1 and 2) so that it will fit on?

Any suggestions/information you can provide would be awesome.