Need help!! memory storage problem

[mixed_gears]

ok. so, my problem is my memory storage. i do a soft reset and i start at 66%. later on during the day is sky rockets to high 70's or lower 80's. WITHOUT running any programs, phone use ONLY!. i have Oxios installed and works the first few time(i.e. mem. up to 80% then use it. back down to 67%). so here are my questions. here are the apps currently installed on my mogul
s2V
Oxios memory
Pocket cm image viewer
google maps
youtubeplay
ms live search
pocket cm contacts
someguy smms
iphone dial pad
cooltek touchpal
htc cube
s2u2
htc home
ms net. cf 3.5

1) can i manually remove some apps that i dont use or need like
Adobe Reader
Get Good
Internet Sharing
Java
Music
On Demand
Software Store

2) i've read around these forums that installing windows mobile 6.1 frees up space or doesnt hog up space like wm 6. can i do an individual install or is it packaged with the new rom? my current Rom version is 3.35.651.2

3) what are the risk of installing the new rom? will everything in my phone be deleted?

4) Someone told me that installing apps on my sd card will make it run smoother. however, everything i installed went back directly to my device. the only apps that actually installed on my sd card are
Live search
oxios
youtubeplay
is there a specific way to get all the other apps to install and run from my mem. card?

if you can answer any of my questions please do so.