new here and need some Canon advice

[flatmtn]

Hi all. I am still clinging to my old Canon Eos film, but cheating for my family and website with a digital point and shoot that finally died on me. I think it's very much time for me to bite the bullet for the digital SLR. I am not new to exposure and metering and such but am old school and pretty new to digital. I have sliver of computer knowledge.
I am looking at the Canon T1i. I think it should be an easy transition from my canon now, and I've got some Q's.
1) I wondered if my lens will work with it for a short time, as I have not much budget to start with. I have a canon 75-300mm EF USM II It's okay if it's slow for the start. Half the time I manually focus anyway.

2) I need some decent video for online clips. I was hoping this would cover both, but what can I edit the video with. It's an .mov file I imagine, right? I have a PC with Windows Vista. DOn't need fancy edit but need to modify, shorten and rearrange clips, overlay sound and keep sound from original as well. need to be able to post to youtube, also, not surprisingly.

3) What's good mid level editing program for the stills. I have used photoshop ages ago, but what are the best choices for Vista. (I do have add on hard drive, so I have room...)

Thanks for any help on this - and redirect me if I need to post my Q's elsewhere. Cool forum. Hope to learn much.