Is there no other way to use flash menus??

apart from what i've read, using an app to 'flash' the phone or smth... which i am unclear of, is there no simpler method?? just asking... really apreciate =) thanks

Nope. You will need to use a program to flash the SWF file into the phone.

if you have some phone without flash lite support you cant have flash menu on this phone, only if you reflashed your phone to phone that supports flash menus....but HW of your phone must be identical with HW of FW of other phone, that supports flash menus...

and if you have phone with support flash, you can use patch to replace dektop/flash folder to "other" folder...

can i use flash menu in k750?

Nope. Only works with Walkman mobiles, from W810i and newer, it also works on the W900i.

so will i be able to get flash menu one w850i ???

^^ yes you can ... using FaR or XS++ just upload to swf files to correct location
lots of guide all over internet and this forum.. check it out..!! Tutorial Section of this forum ! ALso customization of firmware section of this forum

Yep flash themes work on W850i, here tutorial:
Tutorial | W850i Flash Themes Guide Cid/49/51/51/53 - SE-NSE Forums