#1
im 16 and i go to the french school in washington, dc (technically its in bethesda, md). the french system is real intense and 3/5 days im at school from 8:30-5:30. i live about 40 school bus ride away and most of my friends live within 15 min of the school so i don't really have anyone to jam with. i need a new amp anyways cause ive been using my marshall mg10 for 4 years now. im wondering if i should get a 65-75w amp or a 120w combo. most of the time its gonna be sitting in my bedroom but i may play with my friends band occasionally due to the fact that they still cant find another guitarist. and im gonna go to college soon and by then i may get a lot more serious about playing (as in with other people). these are the amps im considering:

http://www.musiciansfriend.com/product/Roland-Cube-60-Guitar-Amp?sku=480197
and
http://www.musiciansfriend.com/product/Crate-Flexwave-Series-FW65-65W-1x12-Guitar-Combo-Amp?sku=481058
for 65 watts

http://www.musiciansfriend.com/product/Peavey-ValveKing-112-Combo-Amp?sku=481442
and
http://www.musiciansfriend.com/product/Crate-Flexwave-FW120-2x12-Guitar-Combo-Amp?sku=481052
the valveking is a tube amp so i guess it'll be around the same volume as the crate.
#2
valve king .hands down, and it will be louder than the crate
actually now that i look at it, i dont know. but the vk is loud enough
#4
budget, umm. no cash right now but probably not more than $500-$600. i listen to A7X, billy talent, breaking benjamin, wolfmother, linkin park, galneryus (japanese power metal) and wolfmother. getting the linkin park sound not so important, i dont play them that much, i just like to listen. but i know it'd be hard to get tones similar to the others, kinda diverse.
#5
Id try out the B=52 AT 112. Its a lot better than the Valveking IMO. The Guitar Center in Rockville MD had some the last time I was down there. Try those out, and If I were you I'd stay away from the Crates, and if possible stick with tube, not modeling or hybrid. If you want better options though, try to look used, because you can get some decent tube combos used on ebay for $500-$600.